LanMountainDesktop/.trae/specs/update-settings-fluent-controls/spec.md

Update Settings Fluent Controls

Goal

Make the Settings > Update page the single user-facing control surface for the host update flow.

Requirements

• The page uses Fluent Avalonia settings controls for update status, release facts, update behavior, and transfer controls.
• Users can choose update channel, download source, update mode, and download thread count.
• Update mode options are:
  • Manual: do not automatically download or install.
  • Silent Download: check and download in the background, then wait for user installation confirmation.
  • Silent Install: check and download in the background, then apply when the app exits.
• Users can opt into forced reinstall. When enabled, the update check targets the current version manifest where available and the UI labels the next payload as reinstall.
• The page displays whether the current payload is an incremental update or reinstall/full installer.
• The page exposes pause, resume, and cancel actions for resumable downloads and install recovery.
• Existing PloNDS/FileMap incremental update behavior remains, but update apply and rollback ownership belongs to the Host. Launcher only selects and starts the current app version.

Acceptance

• UpdateSettingsPage shows Fluent Avalonia controls for channel, mode, thread count, forced reinstall, pause/resume, and cancel.
• UpdateSettingsState persists forced reinstall alongside other update preferences.
• Automatic startup checks skip manual mode, download in silent download/silent install modes, and leave installation to explicit user action or exit-time apply.
• Build succeeds for LanMountainDesktop.slnx.