feat(jobs): mirror delivery_method/ship_via/invoice_strategy on fp.job

Tier 3 of the SO->fp.job persistence audit. Three logistics/billing
fields surface on fp.job as related read-only (not stored) mirrors:

- x_fc_delivery_method - Local Delivery / Shipping Partner / Customer
  Pickup. Cargo classification used by logistics planning.
- x_fc_ship_via - Carrier name (UPS, FedEx, customer pickup, etc.).
- x_fc_invoice_strategy - Deposit / Progress / Net Terms / COD-Prepay.
  Read by the invoicing module's hooks; mirroring on the WO is for
  manager visibility only.

These were intentionally chosen as related (not stored persisted)
because the SO is the authoritative source - the existing downstream
code (delivery + invoicing modules) already reads them off SO directly.
A stored copy would risk drift. Related auto-follows SO updates.

Same three fields also mirrored on sale.order.line as stored related
for per-line list visibility.

Closes the SO->fp.job persistence audit. All 10 operational fields
identified now flow through to the WO (7 stored + populated at confirm,
3 related read-only).

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

fusion_plating/fusion_plating_configurator/models/sale_order_line.py

@@ -684,3 +684,22 @@ class SaleOrderLine(models.Model):
         readonly=True,
         store=True,
     )
+
+    x_fc_delivery_method = fields.Selection(
+        related='order_id.x_fc_delivery_method',
+        string='Delivery Method',
+        readonly=True,
+        store=True,
+    )
+    x_fc_ship_via = fields.Char(
+        related='order_id.x_fc_ship_via',
+        string='Ship Via',
+        readonly=True,
+        store=True,
+    )
+    x_fc_invoice_strategy = fields.Selection(
+        related='order_id.x_fc_invoice_strategy',
+        string='Invoice Strategy',
+        readonly=True,
+        store=True,
+    )