Step 3: Add admin API endpoints for pricing configuration

- Add PricingConfigResponse and PricingConfigUpdate schemas
- Create PricingService with validation logic
- Add GET and PUT endpoints in routes/pricing.py
- Add MANAGE_PRICING permission to admin role
- Register pricing router in main.py
- Add comprehensive API tests for permissions and validation

backend/models/enums.py

@@ -22,6 +22,7 @@ class Permission(str, PyEnum):
 
     # Availability/Exchange permissions (admin)
     MANAGE_AVAILABILITY = "manage_availability"
+    MANAGE_PRICING = "manage_pricing"
     VIEW_ALL_EXCHANGES = "view_all_exchanges"
     CANCEL_ANY_EXCHANGE = "cancel_any_exchange"
     COMPLETE_EXCHANGE = "complete_exchange"

backend/models/role_config.py

@@ -14,6 +14,7 @@ ROLE_DEFINITIONS: dict[str, RoleConfig] = {
             Permission.FETCH_PRICE,
             Permission.MANAGE_INVITES,
             Permission.MANAGE_AVAILABILITY,
+            Permission.MANAGE_PRICING,
             Permission.VIEW_ALL_EXCHANGES,
             Permission.CANCEL_ANY_EXCHANGE,
             Permission.COMPLETE_EXCHANGE,