Update .env.example and PHASE-TRACKING.md for WebUI configuration changes

- Changed WEBUI_URL in .env.example from localhost to the accessible host IP address (http://10.111.0.65:3000) for proper deployment.
- Updated PHASE-TRACKING.md to reflect the new OAuth2-Redirect URLs and clarify the WebUI integration process.

.env.example

@@ -18,6 +18,6 @@ TWITCH_CLIENT_ID=
 TWITCH_CLIENT_SECRET=
 
 # WebUI (apps/webui)
-WEBUI_URL=http://localhost:3000
+WEBUI_URL=http://10.111.0.65:3000
 # Must be at least 32 characters long. Generate e.g. with `openssl rand -hex 32`.
 SESSION_SECRET=