feat(promote-customer-spec): Phase A — recipe + spec foundation

- Add fp.recipe.thickness model (replaces fp.coating.thickness, scoped to recipe root)
- Add spec metadata + bake-relief fields to fusion.plating.process.node (recipe root):
  phosphorus_level, thickness_min/max/uom, thickness_option_ids,
  requires_bake_relief + bake_window_hours/temperature/duration
- Add recipe_ids M2M + print_on_cert to fusion.plating.customer.spec
- Add applicable_spec_ids reverse M2M as inherit in fusion_plating_quality
  (avoids circular dep — core can't reference customer.spec which lives in quality)
- Surface new fields on recipe form ("Specification & Bake" notebook page)
- Surface recipe linkage on customer spec form

Pure additive. Foundation for Phases B-E.

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

fusion_plating/fusion_plating_quality/views/fp_customer_spec_views.xml

@@ -50,6 +50,13 @@
                     <group string="Applicable Processes" name="applicable_processes">
                         <field name="process_type_ids" widget="many2many_tags" nolabel="1"/>
                     </group>
+                    <group string="Applicable Recipes" name="applicable_recipes">
+                        <field name="recipe_ids" widget="many2many_tags" nolabel="1"
+                               options="{'no_create_edit': True}"/>
+                    </group>
+                    <group>
+                        <field name="print_on_cert"/>
+                    </group>
                     <notebook>
                         <page string="Notes">
                             <field name="notes"/>

fusion_plating/fusion_plating_quality/views/fp_process_node_inherit_views.xml

@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+    Copyright 2026 Nexa Systems Inc.
+    License OPL-1 (Odoo Proprietary License v1.0)
+    Part of the Fusion Plating product family.
+
+    Adds the "Applicable Specifications" group to the recipe form
+    (defined in core under the "Specification & Bake" notebook page).
+    Lives here because the field applicable_spec_ids is added by an
+    inherit in this module.
+-->
+<odoo>
+
+    <record id="view_fp_process_node_form_quality_inherit" model="ir.ui.view">
+        <field name="name">fusion.plating.process.node.form.quality.inherit</field>
+        <field name="model">fusion.plating.process.node</field>
+        <field name="inherit_id" ref="fusion_plating.view_fp_process_node_form"/>
+        <field name="arch" type="xml">
+            <xpath expr="//page[@name='spec_metadata']" position="inside">
+                <group string="Applicable Specifications">
+                    <field name="applicable_spec_ids" nolabel="1"
+                           widget="many2many_tags"
+                           options="{'no_create': True}"/>
+                </group>
+            </xpath>
+        </field>
+    </record>
+
+</odoo>