feat(plating): Sub 8 — split receiving vs inspection + box parity

fp.receiving simplifies to box-count-only (new primary state
machine: draft → counted → staged → closed). Legacy
inspecting/accepted/discrepancy/resolved states stay in the
Selection so existing records load without error but are surfaced
behind a manager-only toggle. New box_count_in field + banner
that tells the receiver "count boxes only — parts are inspected
by the racking crew."

New fp.racking.inspection + fp.racking.inspection.line models —
one record per MO, auto-created by mrp.production.create() with
one line per contributing SO line (qty_expected seeded, qty_found
+ condition filled in by the racking crew when they open the boxes).
State: draft → inspecting → done | discrepancy_flagged (flagged
when any line has a non-ok condition or qty variance). Reopen
restricted to Plating Manager.

WO soft gate: first plating WO button_start raises a UserError
when the MO's racking inspection is still Draft or Inspecting.
Plating Manager bypasses; later WOs are not gated.

fp.delivery gains x_fc_box_count_out. action_mark_delivered calls
_fp_check_box_parity which posts a non-blocking chatter warning
when boxes out ≠ boxes in (resolved via job_ref → MO.origin → SO
→ receiving). Warning only — never blocks shipping.

Menu entry: Plating → Operations → Racking Inspection.

Module version bumps:
  fusion_plating_receiving  → 19.0.3.0.0
  fusion_plating_logistics  → 19.0.3.0.0
  fusion_plating_bridge_mrp → 19.0.12.0.0 (+depends receiving)

Smoke on entech: 12/12 assertions pass (one gate test skipped —
MO had no WOs to test) including box-count state machine, inspection
auto-create, lifecycle, discrepancy flag, and box-parity chatter.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

fusion_plating/fusion_plating_receiving/models/__init__.py

@@ -6,5 +6,6 @@
 from . import fp_receiving_damage
 from . import fp_receiving_line
 from . import fp_receiving
+from . import fp_racking_inspection
 from . import sale_order
 from . import mrp_production