fix: Make Swagger server URLs fully configurable

- Add configurable server URL from API_BASE_URL env var
- Make production server optional via PRODUCTION_API_URL env var
- Remove hardcoded https://api.goagel.gov.in
- Document PRODUCTION_API_URL in .env.example

.env.example

@@ -64,6 +64,11 @@ PLATFORM_WALLET_PRIVATE_KEY=
 # NODE_ENV=production
 # FORCE_RESEED=false
 
+# Production API URL for Swagger documentation
+# Only set this when you have a production domain configured
+# Example: https://api.goagel.gov.in
+# PRODUCTION_API_URL=
+
 # External ports (if defaults conflict)
 # API_PORT=3001
 # FRONTEND_PORT=4200