feat(promote-customer-spec): NADCAP recipe lock (Phase A+)

Per client review: NADCAP-qualified recipes need manager-only edit
permission. Word-doc external approval workflow stays outside ERP;
this is the in-app enforcement.

- New field fp.process.node.is_locked (recipe root)
- write() override blocks non-manager edits when recipe root is_locked
  Lock checks via recipe_root_id so child ops/steps are also protected
  Manager bypass via group + env.su (sudo) bypass for system jobs
- Amber "LOCKED — Manager Edit Only" ribbon at top of recipe form
- Toggle on Specification & Bake page under "Change Control (NADCAP)"
- Spec doc updated with Decision 6.5 + backlog from client review:
  approvals list, doc control auto-sync, oven recorder sync, SOP
  word-doc workflow, final-inspection signoff on cert

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

fusion_plating/fusion_plating/models/fp_process_node.py

@@ -4,7 +4,7 @@
 # Part of the Fusion Plating product family.
 
 from odoo import api, fields, models, _
-from odoo.exceptions import ValidationError
+from odoo.exceptions import UserError, ValidationError
 
 from .fp_tz import fp_isoformat_utc
 from ._fp_uom_selection import FP_UOM_SELECTION
@@ -393,6 +393,20 @@ class FpProcessNode(models.Model):
         help='Minimum bake hold time at temperature. Typical 23h.',
     )
 
+    # ---- NADCAP / change-control lock (recipe root) ----
+    # Per client direction: NADCAP-qualified recipes need manager-only
+    # edit permission once they're checked into the system. The Word-doc
+    # change-control workflow lives outside the ERP; this flag is the
+    # ERP-side enforcement point.
+    is_locked = fields.Boolean(
+        string='Locked (Manager-Edit Only)',
+        help='When True, only users in the Manager group can modify '
+             'this recipe (or any of its child operations / steps). '
+             'Use for NADCAP-qualified processes that need '
+             'change-control sign-off before any edit. The flag itself '
+             'can only be toggled by a manager.',
+    )
+
     # NB. `applicable_spec_ids` (reverse of customer.spec.recipe_ids) is
     # defined as an inherit in fusion_plating_quality (the module that
     # owns fusion.plating.customer.spec). Core can't reference it
@@ -591,6 +605,22 @@ class FpProcessNode(models.Model):
         return records
 
     def write(self, vals):
+        # NADCAP / change-control lock — block writes on locked recipes
+        # (and their descendants) for non-manager users. Manager bypass
+        # so the lock can be toggled off.
+        if (self
+                and not self.env.su
+                and not self.env.user.has_group(
+                    'fusion_plating.group_fusion_plating_manager')):
+            for rec in self:
+                root = (rec if (rec.node_type == 'recipe' and not rec.parent_id)
+                        else rec.recipe_root_id)
+                if root and root.is_locked:
+                    raise UserError(_(
+                        "Recipe '%s' is locked (NADCAP / change-control). "
+                        "Only managers can edit it. Ask a manager to "
+                        "unlock the recipe first."
+                    ) % (root.display_name or root.name or '?'))
         meaningful = bool(set(vals.keys()) - self._FP_NON_VERSIONED_FIELDS)
         res = super().write(vals)
         if meaningful and self: