fix(numbering): post-review fixes — credit notes, SO unlink, multi-part grouping, SQL whitelist

- B1: Add Credit Note wizard path was blocked because invoice_origin
  has copy=False and the wizard doesn't set fp_from_so_invoice. Now
  the validator allows reversals when reversed_entry_id points at a
  customer-facing move that itself went through the validator at
  original creation time. account.move._fp_parent_sale_order also
  walks self.reversed_entry_id._fp_parent_sale_order so the credit
  note inherits the parent number (CN-<parent>).

- Bug 1: sale.order.unlink() now blocks deletion when x_fc_parent_number
  is set (matches spec §6.2). Draft quotes remain freely deletable
  per Odoo standard. Applies to all users including admins.

- Bug 2: out_receipt added to CUSTOMER_TYPES so POS-style receipts
  hit the same SO-flow gate as out_invoice / out_refund.

- C1: WO grouping key changed from recipe.id to (recipe.id, part.id,
  coating.id). Bundling lines with different parts under one WO put
  first_line's part_number on the CoC header — silent compliance
  mis-attestation. Now distinct parts always get distinct WOs even
  when they share a recipe.

- C3: SQL whitelist (_FP_COUNTER_FIELD_RE) on _fp_assign_parent_name's
  interpolated counter field name. No user input today; defence in
  depth for future subclasses that might read the name from context.

Verified on entech: parent=30017, credit note = CN-30017,
multi-part SO produces 2 WOs (one per part), confirmed-SO unlink
blocked, out_receipt blocked, whitelist regex enforced.

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

fusion_plating/fusion_plating/__manifest__.py

@@ -5,7 +5,7 @@
 
 {
     'name': 'Fusion Plating',
-    'version': '19.0.18.15.14',
+    'version': '19.0.18.15.15',
     'category': 'Manufacturing/Plating',
     'summary': 'Core plating / metal finishing ERP: facilities, processes, tanks, baths, jobs, operators.',
     'description': """