v1.5.1

Fixed

• Update banner no longer stalls right after a release. The updater now checks whether the winget catalog already has the new version instead of only whether Siphon was installed via winget; since the winget manifest lags GitHub Releases by hours, the banner falls back to the direct .exe download in that window and only routes through winget once it catches up.
• The winget update path now waits for Siphon to exit before upgrading (so the installer can replace the locked executable) and relaunches the app afterward, matching the "Update & restart" button. Previously it quit while the upgrade was still running and never relaunched, so the app just closed and nothing happened.