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/models/__init__.py

@@ -18,7 +18,6 @@ from . import fp_bath_log_line
 from . import fp_bath_parameter
 from . import fp_bath_replenishment_rule
 from . import fp_process_node
-from . import fp_recipe_thickness
 from . import fp_rack
 from . import fp_job
 from . import fp_job_step

fusion_plating/fusion_plating/models/fp_process_node.py

@@ -357,13 +357,10 @@ class FpProcessNode(models.Model):
         [('mils', 'mils'), ('microns', 'microns'), ('inches', 'inches')],
         string='Thickness UoM', default='mils',
     )
-    thickness_option_ids = fields.One2many(
-        'fp.recipe.thickness',
-        'recipe_id',
-        string='Thickness Options',
-        help='Discrete thickness values offered to the estimator on the '
-             'order line for jobs running this recipe.',
-    )
+    # thickness_option_ids removed — fp.recipe.thickness model deleted.
+    # Thickness on the SO line is now a free-text Char range (e.g.
+    # "0.0005-0.0008 mils") that auto-fills from last-used per
+    # (part, customer) or the part's x_fc_default_thickness_range.
 
     # ---- Bake relief — AMS 2759/9 hydrogen embrittlement (recipe root) ----
     requires_bake_relief = fields.Boolean(

fusion_plating/fusion_plating/models/fp_recipe_thickness.py

@@ -1,54 +0,0 @@
-# -*- coding: utf-8 -*-
-# Copyright 2026 Nexa Systems Inc.
-# License OPL-1 (Odoo Proprietary License v1.0)
-# Part of the Fusion Plating product family.
-
-from odoo import api, fields, models
-
-
-class FpRecipeThickness(models.Model):
-    """Discrete thickness option offered for a recipe.
-
-    Replaces fp.coating.thickness. The thickness picker on the SO line
-    is scoped to the chosen recipe, so the operator only sees values
-    that match what the recipe actually produces.
-    """
-    _name = 'fp.recipe.thickness'
-    _description = 'Fusion Plating — Recipe Thickness Option'
-    _order = 'recipe_id, sequence, value'
-
-    recipe_id = fields.Many2one(
-        'fusion.plating.process.node',
-        string='Recipe',
-        required=True,
-        ondelete='cascade',
-        domain="[('node_type', '=', 'recipe'), ('parent_id', '=', False)]",
-    )
-    sequence = fields.Integer(default=10)
-    value = fields.Float(
-        string='Thickness',
-        required=True,
-        digits=(10, 4),
-    )
-    uom = fields.Selection(
-        [('mils', 'mils'), ('microns', 'microns'), ('inches', 'inches')],
-        string='UoM',
-        required=True,
-        default='mils',
-    )
-    label = fields.Char(
-        string='Display Label',
-        compute='_compute_label',
-        store=True,
-        help='Auto-formatted "0.0005 mils" string for the picker dropdown.',
-    )
-    note = fields.Char(string='Note')
-    active = fields.Boolean(default=True)
-
-    @api.depends('value', 'uom')
-    def _compute_label(self):
-        for rec in self:
-            rec.label = f'{rec.value:g} {rec.uom}' if rec.value else ''
-
-    def name_get(self):
-        return [(rec.id, rec.label or '?') for rec in self]