feat(plating): recipe-level cert suppression Booleans

Adds five requires_* Booleans on fusion.plating.process.node
(requires_coc, requires_thickness_report, requires_nadcap_cert,
requires_mill_test, requires_customer_specific), default True.

Recipe is SUPPRESS-ONLY: when False, the recipe never produces that
cert type even if the customer/part requested it. Default True =
existing recipes keep producing the same cert set they produce today.

Surfaced on recipe-level form (node_type == 'recipe'); resolver reads
from job.recipe_id which is always a top-level recipe node.

Post-migrate backfills NULL -> TRUE on existing nodes.

Sub: docs/superpowers/specs/2026-05-27-recipe-cert-toggles-design.md
Task: T2.

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

fusion_plating/fusion_plating/models/fp_process_node.py

@@ -502,6 +502,56 @@ class FpProcessNode(models.Model):
         string='Requires Transition Form',
         help='Sub 12b — opens the transition form before Mark Done.',
     )
+
+    # Certificate Output — recipe-level cert suppression (2026-05-27 sub
+    # docs/superpowers/specs/2026-05-27-recipe-cert-toggles-design.md).
+    # Default True for all five so existing recipes keep producing the
+    # same cert set they produce today. A recipe author flips OFF only
+    # the types the recipe physically never produces (passivation = no
+    # thickness; commodity ENP = no nadcap).
+    #
+    # Precedence (Q1 locked decision): recipe SUPPRESSES ONLY. Customer
+    # / part flags decide what is requested; recipe can remove from that
+    # set but never add. See fp.job._resolve_required_cert_types.
+    #
+    # Surfaced on the recipe form only when node_type == 'recipe'; the
+    # fields exist on every node row but the UX hides them deeper in
+    # the tree to avoid confusing authors. Resolver reads from
+    # job.recipe_id which is always a top-level recipe node.
+    requires_coc = fields.Boolean(
+        string='Requires CoC',
+        default=True,
+        help='When False, this recipe never produces a Certificate of '
+             'Conformance even if the customer/part requested one.',
+    )
+    requires_thickness_report = fields.Boolean(
+        string='Requires Thickness Report',
+        default=True,
+        help='When False, this recipe never produces a thickness report. '
+             'Use for passivation, chemical conversion, anodize seal-only, '
+             'etc. — processes that physically have no plating thickness '
+             'to measure.',
+    )
+    requires_nadcap_cert = fields.Boolean(
+        string='Requires Nadcap Certificate',
+        default=True,
+        help='When False, this recipe never auto-spawns a Nadcap cert. '
+             'Use for commodity recipes that the shop does not run under '
+             'Nadcap accreditation.',
+    )
+    requires_mill_test = fields.Boolean(
+        string='Requires Mill Test Report',
+        default=True,
+        help='When False, this recipe never auto-spawns a Mill Test Report '
+             'cert.',
+    )
+    requires_customer_specific = fields.Boolean(
+        string='Requires Customer-Specific Cert',
+        default=True,
+        help='When False, this recipe never auto-spawns a Customer-Specific '
+             'cert.',
+    )
+
     # Sub 14b — User-extensible Step Kinds (was Selection of 24).
     # 2026-05-20: required + ondelete='restrict' — kind drives gates,
     # workflow milestones, and operator routing. Optional was a foot-gun