[Windows][Updater] Desktop still offers broken 0.5.22 after fixed 0.5.23 release

## Summary

Buzz Desktop on Windows continues to offer **0.5.22** through the in-app updater even though:

- the 0.5.22 Windows package is unusable because its WebView points to a CI-runner `frontendDist` path, and
- 0.5.23 has been released with the Windows packaged-frontend path fix.

This leaves users on an older working build being prompted to install a known-broken update, while the fixed release is not delivered through the updater.

## Environment

- Windows 11 x64
- Current working Buzz Desktop: 0.5.3
- Update offered by Desktop: 0.5.22
- Broken installed build preserved and inspected: 0.5.22
- Fixed GitHub release available: 0.5.23
- Community relay: self-hosted on a remote VPS; relay health is unrelated and remained healthy

## Steps to reproduce

1. Run a working older Buzz Desktop build on Windows.
2. Open the updater or observe the update notification.
3. Accept the offered 0.5.22 update.
4. Relaunch Buzz Desktop.
5. The window renders the Edge WebView `File not found / ERR_FILE_NOT_FOUND` page.
6. Roll back to the older build.
7. Check for updates again: Desktop still offers 0.5.22 rather than 0.5.23.

## Actual behavior

The update channel remains pinned to 0.5.22. Installing it makes the Windows desktop UI unusable because the executable tries to load frontend assets from a nonexistent build-runner path resembling:

```
C:\Users\RUNNER~1\AppData\Local\Temp\buzz-tauri-package-assets-...\dist
```

The relay and community continue running; only the Desktop UI fails.

## Expected behavior

The updater should stop offering 0.5.22 on Windows and deliver 0.5.23 (or a newer verified build). A release known to make the client unusable should be withdrawn from the update feed.

## Impact

Users following the normal in-app update prompt lose access to the Desktop interface and must manually roll back. This creates repeated breakage even though a fixed release exists.

## Related issues

- #7371 — 0.5.22 Windows build-runner path / ERR_FILE_NOT_FOUND
- #7442 — auto-updater does not detect 0.5.23
- #7362, #7377, #7380 — additional reports of the 0.5.22 Windows packaging failure

## Suggested resolution

1. Promote 0.5.23 (or newer) in the updater manifest.
2. Remove or block 0.5.22 from the Windows update path.
3. Add a release check ensuring the packaged WebView entry point does not contain a CI-runner filesystem path.