cli_error gains duration, exit, a locally classified reason and the scoped provider. New provider_read_fail (desktop) and update_result (desktop, menubar, tray) events, enums only.
* feat(desktop): one-click updates through electron-updater on the update-feeds release
* feat(tray): signed one-click updates through tauri-plugin-updater; feed publishing and release docs
* ci(tray): build without the updater key until it is configured
* chore(windows): set the tray updater public key
* ci(windows): skip updater signing in the release build smoke
* ci(windows): build without updater artifacts when no signing key is available
* ci(windows): turn off updater artifacts through TAURI_CONFIG, not CLI flags pwsh mangles
* ci(windows): run tauri build under bash so --no-sign reaches the CLI (pwsh drops the -- separator)
