fix(custom-widgets): harden v2 authoring

.env.example

@@ -62,7 +62,8 @@ TURBO_TELEMETRY_DISABLED=1
 UNSAFE_ENABLE_MOCK_INTEGRATION=true
 
 # Public Workshop API origin used by Homarr's Workshop browser. The default is https://homarr.dev.
-# NEXT_PUBLIC_WORKSHOP_API_URL=http://127.0.0.1:8090
+# This is read when the server starts, including in the production Docker image.
+# WORKSHOP_API_URL=http://127.0.0.1:3003
 
 # Enable demo mode (seeds a demo user "demo"/"demo", a sample board and a mock integration)
 # DEMO_MODE=true