feat(certificates): per-customer document preferences (CHUNK 1/4)

Customers can now pick which shipping-time documents they actually want
instead of the shop remembering it per account. Four booleans on
res.partner (only shown on companies, not contacts):

  x_fc_send_coc              (default True)  Certificate of Conformance
  x_fc_send_thickness_report (default True)  Thickness readings
  x_fc_send_packing_slip     (default True)  Packing slip PDF
  x_fc_send_bol              (default False) Bill of Lading

Surfaced in a "Plating Documents" page on the customer form.

Two downstream gates:

1. fp.notification.template._collect_attachments() now reads the flags
   when attaching CoC / thickness / packing / BoL PDFs to the shipping
   confirmation email. Flags missing on the partner (e.g. legacy
   customers) fall back to the original defaults so nothing regresses.

2. mrp.production.button_mark_done() only auto-creates the quality
   documents the customer wants. A customer that unchecks both CoC and
   thickness gets zero certs auto-generated — shop can still create
   them manually if needed.

Note: today a standalone thickness-only report template doesn't exist,
so when a customer asks for thickness only (CoC off, thickness on) the
dispatcher still attaches the CoC PDF (which carries thickness data)
but with CoC creation gated off. A dedicated thickness-only template
is a follow-up.

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

fusion_plating/fusion_plating_certificates/models/__init__.py

@@ -6,3 +6,4 @@
 from . import fp_thickness_reading
 from . import fp_certificate
 from . import res_config_settings
+from . import res_partner

fusion_plating/fusion_plating_certificates/models/res_partner.py

@@ -0,0 +1,41 @@
+# -*- 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 fields, models
+
+
+class ResPartner(models.Model):
+    """Per-customer preferences for what quality documents are generated
+    and emailed when a job ships.
+
+    Some aerospace customers insist on a full CoC + thickness report;
+    others just want the CoC; some repeat commercial accounts want
+    neither (the PO says "no paperwork required"). Rather than hard-code
+    the shop's policy, each customer controls their own.
+    """
+    _inherit = 'res.partner'
+
+    x_fc_send_coc = fields.Boolean(
+        string='Send Certificate of Conformance',
+        default=True, tracking=True,
+        help='When shipping, auto-generate and email a CoC to this customer.',
+    )
+    x_fc_send_thickness_report = fields.Boolean(
+        string='Send Thickness Report',
+        default=True, tracking=True,
+        help='When shipping, auto-generate and email a thickness report '
+             'with the Fischerscope readings for this job.',
+    )
+    x_fc_send_packing_slip = fields.Boolean(
+        string='Send Packing Slip',
+        default=True, tracking=True,
+        help='Attach the packing slip PDF to the shipping confirmation email.',
+    )
+    x_fc_send_bol = fields.Boolean(
+        string='Send Bill of Lading',
+        default=False, tracking=True,
+        help='Attach the BoL PDF to the shipping confirmation email. '
+             'Usually only for customers that invoice freight separately.',
+    )