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/__manifest__.py

@@ -5,7 +5,7 @@
 
 {
     'name': 'Fusion Plating — Logistics',
-    'version': '19.0.3.5.0',
+    'version': '19.0.3.6.0',
     'category': 'Manufacturing/Plating',
     'summary': (
         'Pickup & delivery for plating shops: vehicle master, driver '