feat(loyalty): attribute transactions to the acting POS tablet

Adds acting_terminal_device_id to loyalty_transactions so the audit
log can distinguish between operations performed via the web terminal
(human user JWT) and operations performed via a paired tablet (device
JWT). The principal-of-record stays the pairing user — existing
reports keep working — and this column adds "which tablet did it"
alongside.

Threaded through every store-API endpoint that creates a transaction
(stamp add/redeem/void, points earn/redeem/void/adjust, enrollment +
welcome bonus, card deactivate/reactivate). The route reads
current_user.terminal_device_id, which the bearer-auth dep populates
when a device JWT is presented. User-token requests leave the column
NULL, as covered by the new test.

Bulk admin operations (GDPR anonymization, bulk deactivate) and Celery
tasks (point expiration) are not threaded — they always come from a
human admin or the scheduler, never a tablet.

- Migration loyalty_011 + LoyaltyTransaction.acting_terminal_device_id
- 9 service signatures gain the optional kwarg
- 8 store-API routes pass it through
- Integration tests: device JWT populates the column, user JWT leaves
  it NULL

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

app/modules/loyalty/routes/api/store.py

@@ -703,7 +703,12 @@ def enroll_customer(
         merchant_id=merchant_id,
     )
 
-    card = card_service.enroll_customer_for_store(db, customer_id, store_id)
+    card = card_service.enroll_customer_for_store(
+        db,
+        customer_id,
+        store_id,
+        acting_terminal_device_id=current_user.terminal_device_id,
+    )
 
     program = card.program
 
@@ -794,6 +799,7 @@ def add_stamp(
         ip_address=ip,
         user_agent=user_agent,
         notes=data.notes,
+        acting_terminal_device_id=current_user.terminal_device_id,
     )
 
     return StampResponse(**result)
@@ -821,6 +827,7 @@ def redeem_stamps(
         ip_address=ip,
         user_agent=user_agent,
         notes=data.notes,
+        acting_terminal_device_id=current_user.terminal_device_id,
     )
 
     return StampRedeemResponse(**result)
@@ -850,6 +857,7 @@ def void_stamps(
         ip_address=ip,
         user_agent=user_agent,
         notes=data.notes,
+        acting_terminal_device_id=current_user.terminal_device_id,
     )
 
     return StampVoidResponse(**result)
@@ -885,6 +893,7 @@ def earn_points(
         ip_address=ip,
         user_agent=user_agent,
         notes=data.notes,
+        acting_terminal_device_id=current_user.terminal_device_id,
     )
 
     return PointsEarnResponse(**result)
@@ -913,6 +922,7 @@ def redeem_points(
         ip_address=ip,
         user_agent=user_agent,
         notes=data.notes,
+        acting_terminal_device_id=current_user.terminal_device_id,
     )
 
     return PointsRedeemResponse(**result)
@@ -943,6 +953,7 @@ def void_points(
         ip_address=ip,
         user_agent=user_agent,
         notes=data.notes,
+        acting_terminal_device_id=current_user.terminal_device_id,
     )
 
     return PointsVoidResponse(**result)
@@ -973,6 +984,7 @@ def adjust_points(
         staff_pin=data.staff_pin,
         ip_address=ip,
         user_agent=user_agent,
+        acting_terminal_device_id=current_user.terminal_device_id,
     )
 
     return PointsAdjustResponse(**result)