Warn against 127.0.0.1/localhost/0.0.0.0 for NATEMPLATE_API_DOMAIN

Those addresses resolve to the simulator or device itself, not the host
Mac. Developers should use their Mac's LAN IP.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: dadachi

README.md

@@ -149,6 +149,8 @@ NATEMPLATE_API_DOMAIN = <your-lan-ip>
 NATEMPLATE_API_PORT   = 3000
 ```
 
+> **Note:** Never use `127.0.0.1`, `localhost`, or `0.0.0.0` for `NATEMPLATE_API_DOMAIN` — those resolve to the iOS Simulator/device itself, not your Mac. Use your Mac's LAN IP (e.g., `192.168.1.6`) so the simulator or a physical device can reach the API server.
+
 Keep the scheme in `xcuserdata` (per-developer, gitignored), not `xcshareddata`. In Xcode, open **Product → Scheme → Manage Schemes…**, find `NativeAppTemplate`, and **uncheck "Shared"**. This moves the scheme (with your local env vars) to `xcuserdata/<user>.xcuserdatad/xcschemes/` so your API settings are not committed. If Xcode staged a deletion of the previously shared scheme, restore it with:
 
 ```bash