WIP: feat(ui): Migrate to new UI implementation

docs/launcher_self_update.md

@@ -14,7 +14,7 @@ launcher. Periodic WinSparkle checks are disabled.
 Pass the public feed URL at build time:
 
 ```powershell
-flutter build windows `
+fvm flutter build windows `
   --dart-define=MOONWELL_API_BASE_URL=https://host `
   --dart-define=MOONWELL_APPCAST_URL=https://host/launcher/updates/appcast.xml
 ```
@@ -91,13 +91,13 @@ Perform Windows signing on the Windows release machine because the package
 invokes WinSparkle's Windows signing utility.
 
 1. Update `pubspec.yaml` to the new `X.Y.Z+N` version.
-2. Run `flutter pub get`, formatting, analysis, and all tests.
+2. Run `fvm flutter pub get`, formatting, analysis, and all tests.
 3. Build Windows with both production `--dart-define` values.
 4. Compile the installer with `ISCC.exe /DMyAppVersion=X.Y.Z`.
 5. Make the private key available outside the repository and sign the artifact:
 
    ```powershell
-   dart run auto_updater:sign_update `
+   fvm dart run auto_updater:sign_update `
      build\installer\moonwell_launcher_X.Y.Z_windows_setup.exe `
      C:\secure-path\dsa_priv.pem
    ```