feat(thickness): single Char range field — drop fp.recipe.thickness picker

Per client direction: every order is a thickness RANGE (e.g.
"0.0005-0.0008 mils" or "5-10 mils"), never a single value. The
old picker model (fp.recipe.thickness with a single 'value' Float)
was modelling the wrong concept and overcrowding the order entry
UI. Replaced with one free-text Char field that auto-fills from
last-used or part default.

DELETED entirely:
- fp.recipe.thickness model (file + view + ACL + manifest entry)
- recipe.thickness_option_ids One2many (the picker source)
- "Thickness Options" inline list on the recipe form
- sale.order.line.x_fc_thickness_id (M2O picker)
- account.move.line.x_fc_thickness_id
- fp.delivery.x_fc_thickness_id
- fp.direct.order.line.thickness_id

ADDED:
- sale.order.line.x_fc_thickness_range (Char) — operator types range
- account.move.line.x_fc_thickness_range — for invoice rendering
- fp.delivery.x_fc_thickness_range — for packing slip
- fp.direct.order.line.thickness_range — for the wizard
- fp.part.catalog.x_fc_default_thickness_range — part default

AUTO-FILL CHAIN (sale.order.line + wizard line):
1. Operator already typed → keep
2. Most recent SO line for (this part, this customer) with a
   non-empty thickness_range → copy that
3. part.x_fc_default_thickness_range → copy
4. Blank — operator types

Implemented as both an @api.onchange (interactive) AND a
create() override (programmatic — wizard, sale_mrp bridge,
imports). Same logic in both paths.

WIZARD push-to-defaults: when "Save as Default" toggle is ticked
on a wizard line, persist the line's thickness_range to
part.x_fc_default_thickness_range so future first-customer orders
get a sensible starting point.

REPORTS: customer_line_header.xml + report_fp_wo_sticker.xml now
print the Char range as-typed (no display_name lookup needed).

KEPT (admin documentation only — doesn't affect order entry):
- recipe.thickness_min, thickness_max, thickness_uom on the recipe
  root: documents the recipe's CAPABILITY range. No UI gate; just
  for spec authors to record what the chemistry can produce.

JOB GROUPING: fp.job auto-create groups SO lines by (recipe, part,
spec, thickness, serial). Updated to key on the thickness_range
Char (stripped) instead of the deleted thickness_id integer.

DB cleanup: --update=base ran on the upgrade, dropping the
fp_recipe_thickness table + the four x_fc_thickness_id columns.
Existing data was already nulled in earlier dev work.

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

fusion_plating/fusion_plating_configurator/models/account_move_line.py

@@ -65,10 +65,9 @@ class AccountMoveLine(models.Model):
         string='Job #', index=True,
         help='Copied from sale.order.line.',
     )
-    x_fc_thickness_id = fields.Many2one(
-        'fp.recipe.thickness',
+    x_fc_thickness_range = fields.Char(
         string='Thickness',
-        help='Copied from sale.order.line for customer-facing invoice PDFs.',
+        help='Carried from the SO line — prints on the invoice PDF.',
     )
     # x_fc_customer_spec_id added by fusion_plating_quality.
     x_fc_revision_snapshot = fields.Char(

fusion_plating/fusion_plating_configurator/models/fp_part_catalog.py

@@ -279,6 +279,14 @@ class FpPartCatalog(models.Model):
     # ---- Direct-order defaults (Phase C — C4) ----
     # x_fc_default_customer_spec_id added by fusion_plating_quality.
     # Legacy default_coating_config_id + default_treatment_ids removed.
+    x_fc_default_thickness_range = fields.Char(
+        string='Default Thickness',
+        help='Default thickness range as free text (e.g. "0.0005-0.0008 mils" '
+             'or "5-10 mils"). Pre-fills the thickness on new sale order '
+             'lines for this part — falls back when no recent order for '
+             'the same (part, customer) pair exists. Updated when the '
+             'wizard\'s "Save as Default" toggle is ticked.',
+    )
 
     # Substrate density mapping (g/cm³) for material weight calculation
     _SUBSTRATE_DENSITY = {

fusion_plating/fusion_plating_configurator/models/sale_order_line.py

@@ -304,12 +304,13 @@ class SaleOrderLine(models.Model):
         help='Shop-floor reference for this line. Auto-sequenced on sale '
              'order confirmation; editable. Blank is allowed.',
     )
-    x_fc_thickness_id = fields.Many2one(
-        'fp.recipe.thickness',
+    x_fc_thickness_range = fields.Char(
         string='Thickness',
-        ondelete='set null',
-        domain="[('recipe_id', '=', x_fc_process_variant_id)]",
-        help="Target thickness. Options come from the line's recipe.",
+        help='Target thickness range as the operator types it, e.g. '
+             '"0.0005-0.0008 mils" or "5-10 mils". Free-form text — '
+             'auto-fills from the last order for this (part, customer) '
+             'pair, falling back to the part\'s default range. Prints '
+             'verbatim on the cert, packing slip, and invoice.',
     )
     x_fc_revision_snapshot = fields.Char(
         string='Revision (snapshot)',
@@ -399,6 +400,32 @@ class SaleOrderLine(models.Model):
                 part = Part.browse(vals['x_fc_part_catalog_id']).exists()
                 if part and part.revision:
                     vals['x_fc_revision_snapshot'] = part.revision
+
+            # Auto-fill thickness range — same logic as the onchange but
+            # for programmatic creators (wizard, sale_mrp, imports).
+            # Resolution: explicit > last-used (part, partner) > part default.
+            if (not vals.get('x_fc_thickness_range')
+                    and vals.get('x_fc_part_catalog_id')):
+                part = Part.browse(vals['x_fc_part_catalog_id']).exists()
+                if part:
+                    # Need partner_id from the parent order
+                    partner_id = False
+                    if vals.get('order_id'):
+                        order = self.env['sale.order'].browse(vals['order_id']).exists()
+                        if order:
+                            partner_id = order.partner_id.id
+                    if partner_id:
+                        recent = self.search([
+                            ('x_fc_part_catalog_id', '=', part.id),
+                            ('order_id.partner_id', '=', partner_id),
+                            ('x_fc_thickness_range', '!=', False),
+                            ('x_fc_thickness_range', '!=', ''),
+                        ], order='create_date desc', limit=1)
+                        if recent:
+                            vals['x_fc_thickness_range'] = recent.x_fc_thickness_range
+                    if (not vals.get('x_fc_thickness_range')
+                            and getattr(part, 'x_fc_default_thickness_range', None)):
+                        vals['x_fc_thickness_range'] = part.x_fc_default_thickness_range
         lines = super().create(vals_list)
         lines._fp_apply_recipe_polish()
         return lines
@@ -473,8 +500,8 @@ class SaleOrderLine(models.Model):
             vals['x_fc_serial_id'] = self.x_fc_serial_id.id
         if self.x_fc_job_number:
             vals['x_fc_job_number'] = self.x_fc_job_number
-        if self.x_fc_thickness_id:
-            vals['x_fc_thickness_id'] = self.x_fc_thickness_id.id
+        if self.x_fc_thickness_range:
+            vals['x_fc_thickness_range'] = self.x_fc_thickness_range
         if self.x_fc_revision_snapshot:
             vals['x_fc_revision_snapshot'] = self.x_fc_revision_snapshot
         # x_fc_customer_spec_id carry-over is handled by an
@@ -576,18 +603,41 @@ class SaleOrderLine(models.Model):
             'target': 'current',
         }
 
-    @api.onchange('x_fc_process_variant_id')
-    def _onchange_recipe_clears_thickness(self):
-        """Clear the thickness picker when recipe changes.
+    @api.onchange('x_fc_part_catalog_id')
+    def _onchange_part_default_thickness(self):
+        """Auto-fill thickness range from last-used or part default.
 
-        Thickness options are scoped to the recipe; a value carried over
-        from a previous recipe would fail its domain.
+        Resolution order (first match wins):
+          1. Operator already typed a value → keep
+          2. Most recent SO line for (this part, this customer) with a
+             non-empty thickness_range → copy that
+          3. Part's x_fc_default_thickness_range → copy
+          4. Blank — operator types
         """
         for line in self:
-            if (line.x_fc_thickness_id
-                    and line.x_fc_thickness_id.recipe_id
-                    != line.x_fc_process_variant_id):
-                line.x_fc_thickness_id = False
+            if line.x_fc_thickness_range:
+                continue
+            if not line.x_fc_part_catalog_id:
+                continue
+            partner = line.order_id.partner_id
+            # 2. Last-used for (part, customer)
+            if partner:
+                recent = self.env['sale.order.line'].search([
+                    ('x_fc_part_catalog_id', '=', line.x_fc_part_catalog_id.id),
+                    ('order_id.partner_id', '=', partner.id),
+                    ('x_fc_thickness_range', '!=', False),
+                    ('x_fc_thickness_range', '!=', ''),
+                    ('id', '!=', line.id or 0),
+                ], order='create_date desc', limit=1)
+                if recent:
+                    line.x_fc_thickness_range = recent.x_fc_thickness_range
+                    continue
+            # 3. Part default
+            part_default = getattr(
+                line.x_fc_part_catalog_id, 'x_fc_default_thickness_range', None,
+            )
+            if part_default:
+                line.x_fc_thickness_range = part_default
 
     def action_generate_serial(self):
         """Generate one new auto-sequenced serial and append it to the M2M.