feat(configurator): auto-load latest part description version on order entry

Wizard line (direct + express) and SO line now pre-fill BOTH internal +
customer-facing from the part's latest version (fallback to
default_specification_text), without clobbering typed text.

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

fusion_plating/fusion_plating_configurator/models/sale_order_line.py

@@ -42,6 +42,20 @@ class SaleOrderLine(models.Model):
                 return tail.lstrip(' \t\r\n-—–:').strip()
         return name
 
+    @api.onchange('x_fc_part_catalog_id')
+    def _fp_onchange_part_load_description(self):
+        """Pre-fill name (customer-facing) + x_fc_internal_description from
+        the part's latest description version, when empty (spec 2026-05-29)."""
+        for line in self:
+            part = line.x_fc_part_catalog_id
+            if not part:
+                continue
+            descs = part._fp_resolve_line_descriptions()
+            if not line.name and descs['customer_facing']:
+                line.name = descs['customer_facing']
+            if not line.x_fc_internal_description and descs['internal']:
+                line.x_fc_internal_description = descs['internal']
+
     x_fc_part_catalog_id = fields.Many2one(
         'fp.part.catalog', string='Part',
     )