feat(loyalty): restructure program CRUD by interface

Move program CRUD from store to merchant/admin interfaces.
Store becomes view-only for program config while merchant gets
full CRUD and admin gets override capabilities.

Merchant portal:
- New API endpoints (GET/POST/PATCH/DELETE /program)
- New settings page with create/edit/delete form
- Overview page now has Create/Edit Program buttons
- Settings menu item added to sidebar

Admin portal:
- New CRUD endpoints (create for merchant, update, delete)
- New activate/deactivate program endpoints
- Programs list has edit and toggle buttons per row
- Merchant detail has create/delete/toggle program actions

Store portal:
- Removed POST/PATCH /program endpoints (now read-only)
- Removed settings page route and template
- Terminal, cards, stats, enroll unchanged

Tests: 112 passed (58 new) covering merchant API, admin CRUD,
store endpoint removal, and program service unit tests.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/modules/loyalty/definition.py

@@ -23,6 +23,13 @@ def _get_admin_router():
     return admin_router
 
 
+def _get_merchant_router():
+    """Lazy import of merchant router to avoid circular imports."""
+    from app.modules.loyalty.routes.api.merchant import router as merchant_router
+
+    return merchant_router
+
+
 def _get_store_router():
     """Lazy import of store router to avoid circular imports."""
     from app.modules.loyalty.routes.api.store import store_router
@@ -119,6 +126,7 @@ loyalty_module = ModuleDefinition(
         ],
         FrontendType.MERCHANT: [
             "loyalty-overview",  # Merchant loyalty overview
+            "loyalty-settings",  # Merchant loyalty settings
         ],
     },
     # New module-driven menu definitions
@@ -192,6 +200,13 @@ loyalty_module = ModuleDefinition(
                         route="/merchants/loyalty/overview",
                         order=10,
                     ),
+                    MenuItemDefinition(
+                        id="loyalty-settings",
+                        label_key="loyalty.menu.settings",
+                        icon="cog",
+                        route="/merchants/loyalty/settings",
+                        order=20,
+                    ),
                 ],
             ),
         ],
@@ -253,6 +268,7 @@ def get_loyalty_module_with_routers() -> ModuleDefinition:
     during module initialization.
     """
     loyalty_module.admin_router = _get_admin_router()
+    loyalty_module.merchant_router = _get_merchant_router()
     loyalty_module.store_router = _get_store_router()
     loyalty_module.platform_router = _get_platform_router()
     loyalty_module.storefront_router = _get_storefront_router()