fix: plane space SSR, static path, live server config, update script

- Add plane-space systemd service for SSR (react-router-serve on port 3002)
- Fix nginx /spaces/ to proxy to plane-space instead of static files
- Fix nginx /static/ alias to correct Django collectstatic path
- Fix plane-live EnvironmentFile to /opt/plane/.env
- Fix plane-live ExecStart to use start.mjs
- Update script: backup/restore all .env files, include plane-space
- Update script: add configure_instance after migrations
- Split JSON notes for god-mode and credentials

frontend/public/json/plane.json

@@ -37,7 +37,11 @@
             "type": "info"
         },
         {
-            "text": "Configuration file is at: `/opt/plane/apps/api/.env`. Credentials are saved to `~/plane.creds`.",
+            "text": "Admin panel (God Mode) is available at `/god-mode/` for instance configuration.",
+            "type": "info"
+        },
+        {
+            "text": "Credentials are saved to `~/plane.creds`.",
             "type": "info"
         }
     ]