feat(configurator): per-part description version model + part load/save helpers

fp.part.description.version: immutable per-part snapshots with version_no/
is_latest maintained in create(), titled "<SO#> · <date>". fp.part.catalog
gains description_version_ids + _fp_resolve_line_descriptions (load latest,
fallback to default_specification_text) and _fp_save_description_version
(dedup + sync default). ACL mirrors fp.sale.description.template.

Tests deferred to entech (local Docker unavailable this session).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

fusion_plating/fusion_plating_configurator/__manifest__.py

@@ -5,7 +5,7 @@
 
 {
     'name': 'Fusion Plating — Configurator',
-    'version': '19.0.22.7.1',
+    'version': '19.0.22.8.0',
     'category': 'Manufacturing/Plating',
     'summary': 'Quotation configurator with part catalog, coating configs, and formula-based pricing engine.',
     'description': """