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+# Sub 2 — Part Data Model Overhaul
+
+**Date:** 2026-04-21
+**Module scope:** `fusion_plating_configurator`, `fusion_plating_reports`, `fusion_plating_bridge_mrp` (cert-resolution wiring)
+**Status:** Design approved; ready for implementation plan
+**Predecessor context:** Fine-Tuning Initiative, entry in `fusion_plating/CLAUDE.md`
+
+---
+
+## 1. Scope
+
+Four gaps from the Fine-Tuning running plan:
+
+| Gap | Summary |
+|---|---|
+| **2b** | Part Number + Revision become required; Part Name becomes optional |
+| **2c** | Dual descriptions (internal + customer-facing) on every description-template row, flowing to SO line |
+| **2d** | Per-part `certificate_requirement` with `inherit` fallback to the partner's existing flags |
+| **4** | "SKU" relabel to "Part Number" in UI; customer-facing reports print `part_number`, not `default_code` |
+
+### Out of scope (moved to later sub-projects)
+
+- Part's default process / Process Composer → **Sub 3**
+- Contract Review workflow → **Sub 4**
+- Order-line additions (serial, job#, thickness dropdown, revision picker) → **Sub 5**
+- Contact Profiles and per-location notifications → **Sub 6**
+
+---
+
+## 2. Data Model Changes
+
+### 2.1 `fp.part.catalog` (customer parts library)
+
+```
+part_number : Char, required=True # was optional
+revision : Char, required=True, default='A' # was optional
+name : Char, required=False # was required
+
++ certificate_requirement : Selection(
+ ('inherit', 'Inherit from Customer'),
+ ('none', 'No Certificate'),
+ ('coc', 'CoC Only'),
+ ('coc_thickness', 'CoC + Thickness Report'),
+ ), default='inherit', tracking=True
+```
+
+### 2.2 `fp.sale.description.template` (Descriptions tab repeater)
+
+```
+description : REMOVED (migrated out and dropped)
+
++ internal_description : Text, required=True
++ customer_facing_description : Text, required=True
+```
+
+### 2.3 `sale.order.line` (Odoo standard, extended)
+
+```
+name : (Odoo native, already required. Clarified
+ semantically as THE customer-facing
+ description — no repurpose, just formal
+ naming.)
+
++ x_fc_internal_description : Text, required=True
++ x_fc_description_template_id : Many2one('fp.sale.description.template')
+ (which template row the estimator picked)
+```
+
+### 2.4 Explicitly NOT changing
+
+- `product.product` / `product.template.default_code` — untouched. The generic service products (EN Plating, Chrome, etc.) keep their SKUs.
+- Revision chain (`parent_part_id`, `is_latest_revision`, `revision_ids`) — kept as-is (Sub 5 consumes it for the revision picker).
+- `fp.part.catalog.notes` Html — kept as freeform drawer notes, not part of the description system.
+- Partner-level cert flags (`res.partner.x_fc_send_coc`, `x_fc_send_thickness_report`) — kept as the fallback layer for `certificate_requirement = 'inherit'`.
+
+---
+
+## 3. Migration Strategy
+
+Runs once via `post_init_hook` on the module upgrade. All steps idempotent (NULL/empty guards). Safe to re-run.
+
+### Step 1 — Backfill `fp.part.catalog.part_number`
+
+```sql
+UPDATE fp_part_catalog
+SET part_number = name
+WHERE part_number IS NULL OR part_number = '';
+```
+
+Defensible: before this change, `name` was the part identifier. Copy over so `required=True` doesn't reject existing records on upgrade.
+
+### Step 2 — Backfill `fp.part.catalog.revision`
+
+```sql
+UPDATE fp_part_catalog
+SET revision = 'A'
+WHERE revision IS NULL OR revision = '';
+```
+
+### Step 3 — Split `fp.sale.description.template.description`
+
+For every template row with non-empty `description`:
+
+```
+internal_description := (original description value)
+customer_facing_description := (original description value)
+```
+
+Both fields start with the same text. Estimators separate internal workflow text from customer text over time. The old `description` column is dropped in the same migration.
+
+### Step 4 — Backfill `sale.order.line.x_fc_internal_description`
+
+For every SO line in any state:
+
+```
+x_fc_internal_description := name (starter, copy from the existing line description)
+```
+
+The `required=True` constraint applies to **new lines only** — migration flag skips enforcement on historical records so upgrades don't fail on old orders.
+
+### Step 5 — Default cert requirement
+
+Every existing `fp.part.catalog` record gets `certificate_requirement = 'inherit'`. Zero behaviour change for in-flight jobs: the cert cascade still reads partner toggles until a shop admin explicitly sets a part to something other than `inherit`.
+
+---
+
+## 4. UI Changes
+
+### 4.1 Part form (`fp.part.catalog`)
+
+Top identity block:
+
+```
+Part Number* [required] │ Revision* [required, default 'A']
+Part Name [optional] │ Customer [required]
+```
+
+New "Quality & Delivery" group:
+
+```
+Certificate Requirement: [Inherit from Customer ▾]
+ options: Inherit / None / CoC / CoC + Thickness
+Help tooltip: "Inherit reads the customer's default
+ (Partner → Plating Documents tab)."
+```
+
+Descriptions tab — the existing repeater gains two columns:
+
+| Template Name | Category | Internal Description | Customer-Facing Description | Used | Active |
+|---|---|---|---|---|---|
+
+Both description columns required to save a row. Hint above the table:
+
+> "Internal = what the shop floor sees on the WO / traveler. Customer-Facing = what prints on SO, invoice, packing slip."
+
+### 4.2 Direct-Order Wizard + SO Line form
+
+Per line:
+
+- Part picker (unchanged)
+- **Description Template** dropdown — lists active templates where `part_catalog_id == the chosen part`. Partner-wide and coating-wide templates (which the data model allows) are **not** shown at order entry; the dropdown is narrowed to per-part templates to match the shop's mental model ("canned descriptions for this part").
+- **Customer-Facing Description** text box — prefilled from template, editable
+- **Internal Description** text box — prefilled from template, editable
+
+If the part has zero templates, both boxes start blank and the estimator types them. Both required before save.
+
+### 4.3 Universal SKU → Part Number relabel
+
+- Fusion Plating form / list / search views: `string="SKU"` → `string="Part Number"` on fields referencing `fp.part.catalog.part_number`.
+- Customer-facing reports: line rendering flows through the new QWeb macro (§6.1) — prints `part_number + revision + name` (customer-facing desc), no `[default_code]`, no product display name.
+- Internal reports: show everything — part number, revision, customer-facing description, internal description, service product name, service SKU.
+- Odoo-native screens (inventory, warehouse, product selector): untouched. Keep showing `default_code` as "SKU". Customer never sees these.
+
+---
+
+## 5. Certificate-Requirement Resolution (Runtime)
+
+### 5.1 Single-source resolver (Defensive Measure 1)
+
+All cert-related decisions route through one method on `mrp.production`:
+
+```
+def _fp_resolve_cert_requirement(self):
+ """Returns (want_coc: bool, want_thickness: bool) for this MO.
+
+ Walks SO lines to collect each part's certificate_requirement.
+ Part-level wins; 'inherit' falls back to partner toggles.
+ Multi-line MO: strictest wins.
+ """
+```
+
+### 5.2 Resolution order
+
+```
+1. Walk MO → origin (SO name) → sale.order → sale.order.lines → x_fc_part_catalog_id.
+2. For each line's part:
+ if part.certificate_requirement != 'inherit':
+ want_coc_line = part.certificate_requirement in ('coc', 'coc_thickness')
+ want_thickness_line = part.certificate_requirement == 'coc_thickness'
+ else:
+ # Fallback to partner-level flags
+ want_coc_line = partner.x_fc_send_coc
+ want_thickness_line = partner.x_fc_send_thickness_report
+
+3. Multi-line MO — strictest wins:
+ want_coc = any(want_coc_line across lines)
+ want_thickness = any(want_thickness_line across lines)
+```
+
+### 5.3 Callers (must use the resolver)
+
+- `_fp_generate_cert_pdf` in `fusion_plating_bridge_mrp/models/mrp_production.py` (cert cascade on MO done)
+- QC gate's thickness-required check (if/when it reads partner flags today — audit during implementation)
+- Notification routing for auto-email (future Sub 6 will hook here)
+
+### 5.4 Multi-line and fallback cases
+
+- **Multi-line MO** — strictest wins so a customer never gets less paperwork than promised for any part in the batch.
+- **MO with no SO link** (manual MO) — falls back to `mo.partner_id` if set, else `want_coc=True, want_thickness=False` as safe default.
+
+### 5.5 Backward compatibility
+
+Every existing part has `certificate_requirement = 'inherit'` after migration. The resolver falls through to partner toggles exactly as today. No behaviour change for any shipping job until a shop admin explicitly changes a part's cert requirement.
+
+---
+
+## 6. Report Impact
+
+### 6.1 Shared QWeb line-header macro (Defensive Measure 2)
+
+New template in `fusion_plating_reports`:
+
+```xml
+
+```
+
+All four customer-facing report line renderers call ``. When Sub 5 adds the revision picker (and with it the revision snapshot on the SO line), the macro is updated once and all reports follow.
+
+### 6.2 Per-report changes
+
+| Report | Audience | Change |
+|---|---|---|
+| `report_fp_sale.xml` | Customer | Line header via macro: `part_number + revision + name`. Skip `[default_code]`, skip product display name. |
+| `report_fp_invoice.xml` | Customer | Same (via macro) |
+| `report_fp_packing_slip.xml` | Customer | Same (via macro) |
+| `report_fp_bol.xml` | Customer | Same (via macro) |
+| `report_fp_work_order.xml` | Internal (operator) | Keep product/service name + `default_code`. Add `part_number`, `revision`, `name` (customer-facing desc), `x_fc_internal_description` (ops workflow). |
+| `report_fp_job_traveller.xml` | Internal | Same as work order. |
+| `report_coc.xml` | Customer | Audit — reads `doc.part_number` on `fp.certificate`. Spot-check that the cert model populates `part_number` from `sale_order_line.x_fc_part_catalog_id.part_number`. No change expected. |
+| `report_fp_receipt.xml` | Customer | Customer macro treatment. |
+
+### 6.3 Fallback for non-part lines
+
+The macro's fallback branch renders the generic product name for lines without `x_fc_part_catalog_id` (rush fees, freight, expedite). Those lines were never meant to show a part number.
+
+---
+
+## 7. Testing Strategy
+
+### 7.1 Migration tests (one-shot, runs on upgrade)
+
+- `fp.part.catalog` with empty `part_number` → `part_number = name` after migration
+- `fp.part.catalog` with empty `revision` → `revision = 'A'` after migration
+- `fp.sale.description.template` rows with text in `description` → both `internal_description` AND `customer_facing_description` hold that same text; old column gone
+- Confirmed/done SO lines get `x_fc_internal_description = name` backfilled
+- Every existing part ends with `certificate_requirement = 'inherit'`
+- Running the migration a second time is a no-op (idempotency)
+
+### 7.2 Unit tests
+
+- New part without `part_number` → save rejected (UserError / validation)
+- New part without `revision` → save rejected
+- New part without `name` → saves fine (optional)
+- Description template row: both descriptions must be non-empty
+- SO line: both `name` AND `x_fc_internal_description` must be non-empty
+- Cert resolution: part `coc_thickness` + partner `send_coc=False` → result `(True, True)` — part wins
+- Cert resolution: part `inherit` + partner `send_coc=True, send_thickness=False` → result `(True, False)` — falls through
+- Cert resolution: multi-line MO with parts `none` + `coc_thickness` → result `(True, True)` — strictest wins
+- Cert resolution: MO with no SO link → safe fallback
+
+### 7.3 End-to-end smoke (odoo-shell scripts, pattern from QC suite)
+
+- Direct order → SO confirm → MO confirm → MO done → CoC generated with customer part number on page 1, no `[default_code]`
+- Same flow with `certificate_requirement = 'none'` on the part → no CoC generated even if partner has `send_coc=True`
+- Order entry: pick a description template row → both fields populate on the SO line → save → reopen → both fields persist → customer SO PDF shows only the customer-facing description
+- Two customers both add a part numbered `WIDGET-001` at different revisions → no collision (different fp.part.catalog records; default_code on the service product is unchanged)
+
+### 7.4 Regression on Phase 1–3 (QC work)
+
+After the Sub 2 migration, re-run:
+
+- `fp_qc_smoke.py` (9-step smoke)
+- `fp_qc_e2e.py` (8-case edge suite)
+- `fp_full_workflow.py` (full lifecycle)
+
+All must stay green. Sub 2 only wires cert resolution through a new helper — QC checklist logic is untouched.
+
+---
+
+## 8. Defensive Measures (Prevent Rework When Later Subs Land)
+
+1. **Single-source cert resolution** (§5.1) — `_fp_resolve_cert_requirement` is the only place partner-level fallback is read. When Sub 6 restructures partner flags into per-location or per-contact permissions, one function updates — no call-site hunt.
+2. **Shared QWeb macro** (§6.1) — all four customer-facing reports render the line header through one template. Sub 5's revision picker updates the macro, all reports follow.
+3. **Idempotent migration** (§3) — safe to re-run; doesn't fight future sub-project migrations.
+4. **Additive SO line fields** — `x_fc_internal_description`, `x_fc_description_template_id` sit alongside future Sub 5 fields (`x_fc_serial_number`, `x_fc_job_number`, `x_fc_thickness`, `x_fc_revision_snapshot`) with zero touchpoints.
+5. **Clean removal of old `description` column** — migrated then dropped in the same migration. No deprecated-field confusion later.
+
+---
+
+## 9. Files Touched (Anticipated)
+
+### Models
+- `fusion_plating_configurator/models/fp_part_catalog.py` — field changes (part_number / revision required, name optional, + certificate_requirement)
+- `fusion_plating_configurator/models/fp_sale_description_template.py` — field split
+- `fusion_plating_configurator/models/sale_order_line.py` — add `x_fc_internal_description`, `x_fc_description_template_id`
+- `fusion_plating_bridge_mrp/models/mrp_production.py` — add `_fp_resolve_cert_requirement`; rewire `_fp_generate_cert_pdf` to call it
+
+### Views
+- `fusion_plating_configurator/views/fp_part_catalog_views.xml` — required markers, cert requirement field, relabels
+- `fusion_plating_configurator/views/fp_part_catalog_views.xml` (Descriptions tab) — two-column repeater
+- `fusion_plating_configurator/views/sale_order_views.xml` — SO line internal-description field
+- `fusion_plating_configurator/wizard/fp_direct_order_wizard_views.xml` — description-template picker + dual-description inputs
+- Wherever "SKU" appears in views → relabel to "Part Number"
+
+### Reports
+- `fusion_plating_reports/report/report_fp_sale.xml` — use macro
+- `fusion_plating_reports/report/report_fp_invoice.xml` — use macro
+- `fusion_plating_reports/report/report_fp_packing_slip.xml` — use macro
+- `fusion_plating_reports/report/report_fp_bol.xml` — use macro
+- `fusion_plating_reports/report/report_fp_work_order.xml` — add internal description, keep product/default_code
+- `fusion_plating_reports/report/report_fp_job_traveller.xml` — same as WO
+- `fusion_plating_reports/report/customer_line_header.xml` — NEW macro
+
+### Migration
+- `fusion_plating_configurator/migrations/19.0.X.X.X/post-migration.py` — all five migration steps
+- `fusion_plating_configurator/hooks.py` — register `post_init_hook` if not already present
+
+### Security
+- No new models, so no new ACL rows needed. Existing `fp.part.catalog` and `fp.sale.description.template` ACLs already cover the new fields.
+
+### Manifest
+- `fusion_plating_configurator/__manifest__.py` — bump version; register new view / wizard changes
+- `fusion_plating_reports/__manifest__.py` — register new macro file
+- `fusion_plating_bridge_mrp/__manifest__.py` — bump version
+
+---
+
+## 10. Rollout
+
+1. Bump version on all three affected modules.
+2. Push to entech via standard deploy: `systemctl stop odoo` → `odoo -d admin -u fusion_plating_configurator,fusion_plating_reports,fusion_plating_bridge_mrp --stop-after-init` → clear asset cache → `systemctl start odoo`.
+3. Verify migrations ran: count backfilled records against expected.
+4. Run the smoke + E2E + regression suites.
+5. Commit + push when green.
+
+---
+
+## 11. Success Criteria
+
+- Every part on the system has a non-empty `part_number` and `revision`.
+- The Descriptions tab on every part shows the two-column repeater; old single-column layout is gone.
+- Creating a sale order without filling both descriptions on each line is rejected.
+- Customer-facing CoC / SO / invoice / packing slip / BoL never print Odoo's internal SKU.
+- Setting a part's `certificate_requirement` to `none` suppresses CoC generation on MO done, even if the partner has `x_fc_send_coc=True`.
+- Phase 1–3 QC regression suite stays fully green.
+
+---
+
+## 12. Open Questions (None Blocking)
+
+All clarifying questions from the brainstorm (Q1–Q6) are answered. No blocking open questions. Possible implementation-time discoveries (flagged for the plan, not for the spec):
+
+- Exact list of QWeb reports that currently print `default_code` as a line-prefix (grep during implementation; the macro swap might touch one or two more than listed in §6.2).
+- Whether any third-party portal template also renders line headers (unlikely; portal jobs show job-level data not line-level, but worth a sanity grep).
+
+These are discovery items, not design decisions.
diff --git a/fusion_plating/CLAUDE.md b/fusion_plating/CLAUDE.md
index 03ec644b..029037e6 100644
--- a/fusion_plating/CLAUDE.md
+++ b/fusion_plating/CLAUDE.md
@@ -356,3 +356,82 @@ See `K:\Github\RePackaged-Odoo\CLAUDE.md` for full details. Key points:
- Phone-home/telemetry gutted
- `web_enterprise` and `mail_enterprise` are installed on odoo-entech
- Addons path includes: `_dependencies`, `accounting`, `inventory_manufacturing`, `hr`, `sales`, `ai`, `fusion_backend`, `custom`, `website`
+
+## Fine-Tuning Initiative (Started 2026-04-21)
+
+System-wide UX gap closure. Running PLAN → SPEC → IMPLEMENT per sub-project so we don't
+rewrite code as new requirements surface. Each sub-project has its own design doc in
+`docs/superpowers/specs/` and its own implementation plan before any code lands.
+
+### Sub-Project Roadmap
+| # | Sub-project | Status | Gaps |
+|---|---|---|---|
+| 1 | Direct Order Wizard fix (no auto-confirm/auto-email) | Pending | Gap 1 |
+| 2 | Part Data Model Overhaul (part#/rev required, dual descriptions, per-part cert requirement, SKU→Part Number on customer docs) | Design approved 2026-04-21 | 2b, 2c, 2d, 4 |
+| 3 | Default Process + Composer per part (reuse recipe tree) | Pending | 2e, 2f |
+| 4 | Contract Review two-portion workflow (QA Assistant + QA Manager; pre-production gate) | Pending | 2i |
+| 5 | Order-line fields (serial, job#, thickness dropdown, revision picker) | Pending | 5, 6, Q2 |
+| 6 | Contact Profiles & Communication Routing (sub-contacts + per-location notification lists + global contacts) | Pending | client transcript A/B/C |
+| 7 | IoT tuning (configurable polling interval 15–30 min, seed 6–10 tank sensors) | Pending | client transcript D |
+| 8 | Receiving / Inspection / QC flow restructure (split receiving vs inspection; racking crew inspects, not receiver) | Pending | client transcript E |
+| ∞ | First-off / last-off QC | Deferred | client transcript F |
+| ∞ | VEC machine auto-ingest (Word-format thickness report from network-connected XRF; different machine from Fischerscope) | Deferred | client transcript G |
+
+### Sub 2 Locked Decisions (2026-04-21)
+
+| Q | Decision |
+|---|---|
+| Q1 — Cert requirement precedence | Part wins; partner is fallback. New selection `certificate_requirement` on `fp.part.catalog`: `inherit` / `none` / `coc` / `coc_thickness`. Default `inherit` preserves current behaviour for existing records. |
+| Q2 — Revision handling | Keep existing chain (`parent_part_id`, `is_latest_revision`, `revision_ids`). Out-of-scope for Sub 2. The "revision picker at order entry" moves to Sub 5. |
+| Q3 — Required-field flip | Strict + backfill. On upgrade: `part_number = name` if empty; `revision = 'A'` if empty. Then `required=True` for both. `name` becomes optional. |
+| Q4 — Descriptions shape | Split `fp.sale.description.template.description` into `internal_description` + `customer_facing_description`. Repeater on the part's Descriptions tab gains two columns. Old `description` column dropped in migration. |
+| Q5 — SKU vs Part Number | Use `fp.part.catalog.part_number` directly as the source of truth. Don't sync to `default_code`. Customer-facing reports print `part_number`; internal reports keep showing `default_code` (service code). Odoo-native screens untouched. |
+| Q6 — Description required at order entry | **Both required.** SO line carries `name` (customer-facing, already Odoo standard) + new `x_fc_internal_description` (ops workflow). Both required before save. |
+
+### Sub 2 Defensive Measures (Prevent Rework When Later Subs Land)
+
+1. **Single-source cert resolution function** — `mrp.production._fp_resolve_cert_requirement(self)` returns `(want_coc, want_thickness)`. Every caller (cert cascade, QC gate, notification routing) goes through this. When Sub 6 restructures partner-level flags into location / contact permissions, one function updates — no call-site hunt.
+2. **Shared QWeb line-header macro** — `fusion_plating_reports.customer_line_header` renders `part_number + revision + customer-facing description` with fallback to product name for non-part lines. All 4 customer-facing reports (SO, invoice, packing slip, BoL) call the macro. Sub 5's revision picker updates the macro once, all reports follow.
+3. **Isolated migration** — Sub 2's `post_init_hook` is idempotent (NULL/empty checks). Safe to re-run. Doesn't fight Sub 3/4/5/6 migrations.
+4. **Additive SO line fields** — `x_fc_internal_description`, `x_fc_description_template_id` sit alongside future Sub 5 fields (`x_fc_serial_number`, `x_fc_job_number`, `x_fc_thickness`, `x_fc_revision_snapshot`) with zero touchpoints.
+5. **Clean removal of old `description` column** — migrated then dropped. Not kept as deprecated. One clean break now beats two migrations later.
+
+### Sub 6 Preview — Contact Profiles & Communication Routing (client transcript A/B/C)
+- Sub-contacts under `res.partner` with per-contact permissions: certs / QC / quotes+SO / invoices.
+- Multiple delivery locations per customer; each location has its own notification list.
+- Global contact (company-level + location-level) gets all communications.
+- Will restructure or augment the partner-level `x_fc_send_coc` / `x_fc_send_thickness_report` flags that Sub 2 currently falls back to. Sub 2's `_fp_resolve_cert_requirement` is the update point.
+
+### Sub 7 Preview — IoT Tuning (client transcript D)
+- 6–10 active tanks (of ~20–25 total) need continuous monitoring.
+- Polling interval: **30 minutes acceptable, 15 minutes ideal.** Configurable per tank.
+- Temperature, pH, nickel concentration — all on automated controller (existing `fusion_plating_iot` module).
+- Work scope: ensure per-sensor interval field exists + defaults + seed 6–10 tank.sensor records.
+
+### Sub 8 Preview — Receiving / Inspection / QC Restructure (client transcript E)
+**Current flow (wrong):** Direct order → receiving entry → receiver inspects on arrival.
+**Correct flow:**
+1. Customer ships parts in boxes. Receiver counts boxes (does NOT inspect individual parts).
+2. Boxes sit in staging until racking.
+3. Racking crew opens boxes, inspects each part as they load racks (inspection ≠ receiving).
+4. Parts go through plating process.
+5. Post-plate QC on machine (thickness / depth / coating thickness) — existing QC gate (Phase 1–3 work).
+6. Pack back into the SAME boxes they arrived in. Same qty out as in.
+
+**Implication:** The current `fusion_plating_receiving` module conflates receiving + inspection. Sub 8 splits them. Racking-time inspection becomes its own record, linked to WOs not to receiving.
+
+### Deferred Items (Future)
+- **First-off / last-off QC** — first and last part of each batch get full QC inspection; middle parts sampled. Not priority.
+- **VEC machine auto-ingest** — different from Fischerscope. Exports a Word doc (picture + data) named `workorder_PO.docx` to a network share. Plan: auto-scan the share, parse, attach to QC as thickness_report. Defer until core flow is solid.
+
+### Client-Confirmed Operational Thresholds
+- Tank polling: 15–30 min, half-hour acceptable
+- Active tanks: 6–10 (not all 20–25)
+- Boxes round-trip: parts ship back in the same boxes they arrived in, same quantity per box
+
+### How to Resume This Work in a Fresh Session
+1. Read this section (Fine-Tuning Initiative).
+2. Check the sub-project status table — which sub is in flight.
+3. Read the corresponding spec in `docs/superpowers/specs/YYYY-MM-DD-sub-*-design.md`.
+4. Read the implementation plan if one exists.
+5. Continue from the next un-checked step.