feat(numbering): wire CoC/RCV/DLV/PU into parent-numbered mixin + rename counters

Per-model counter fields on sale.order renamed to x_fc_pn_*_count
to avoid collision with pre-existing compute fields of the same
short name in bridge_mrp / receiving / configurator (silent
compute-override was suppressing the storage). 4 child models
(fp.certificate, fp.receiving, fusion.plating.delivery,
fusion.plating.pickup.request) now derive names as PFX-<parent>
with -NN suffix from the 2nd onward.

fusion.plating.pickup.request gains a sale_order_id field
(optional) so pickups created against an SO get parent-derived
names, while standalone pickups (pre-SO) fall back to PU/YYYY/NNNN.

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

fusion_plating/fusion_plating_logistics/models/fp_pickup_request.py

@@ -21,16 +21,26 @@ class FpPickupRequest(models.Model):
     """
     _name = 'fusion.plating.pickup.request'
     _description = 'Fusion Plating — Pickup Request'
-    _inherit = ['mail.thread', 'mail.activity.mixin']
+    _inherit = ['mail.thread', 'mail.activity.mixin', 'fp.parent.numbered.mixin']
     _order = 'requested_date desc, id desc'
 
     name = fields.Char(
         string='Reference',
         required=True,
         copy=False,
-        default=lambda self: self._default_name(),
+        default='New',
         tracking=True,
     )
+    sale_order_id = fields.Many2one(
+        'sale.order',
+        string='Sale Order',
+        ondelete='set null',
+        index=True,
+        help='Sale order this pickup is associated with. Pickup may be '
+             'created BEFORE the SO exists; in that case the '
+             'parent-number naming falls back to the standalone '
+             'PU/YYYY/NNNN sequence and the link can be set later.',
+    )
     partner_id = fields.Many2one(
         'res.partner',
         string='Customer',
@@ -126,8 +136,39 @@ class FpPickupRequest(models.Model):
         compute='_compute_custody_count',
     )
 
+    # ------------------------------------------------------------------
+    # Parent-numbered mixin hooks
+    # ------------------------------------------------------------------
+    def _fp_parent_sale_order(self):
+        return self.sale_order_id
+
+    def _fp_name_prefix(self):
+        return 'PU'
+
+    def _fp_parent_counter_field(self):
+        return 'x_fc_pn_pickup_count'
+
+    @api.model_create_multi
+    def create(self, vals_list):
+        for vals in vals_list:
+            if not vals.get('name'):
+                vals['name'] = 'New'
+        records = super().create(vals_list)
+        for rec in records:
+            if rec.name and rec.name != 'New':
+                continue
+            if not rec._fp_assign_parent_name():
+                seq = self.env['ir.sequence'].next_by_code('fusion.plating.pickup.request') or 'New'
+                self.env.cr.execute(
+                    "UPDATE fusion_plating_pickup_request SET name = %s WHERE id = %s",
+                    (seq, rec.id),
+                )
+                rec.invalidate_recordset(['name'])
+        return records
+
     @api.model
     def _default_name(self):
+        """Retained for legacy callers; new flow uses the create() override."""
         seq = self.env['ir.sequence'].next_by_code('fusion.plating.pickup.request')
         return seq or '/'