SubMiner/changes/sync.md

type: added area: sync

• Added cross-machine immersion sync for stats and watch history over SSH, available as a window (Sync Stats & History in the tray menu, or subminer sync --ui) and as a command (subminer sync <host>, with --push / --pull for one-way insert-only transfers). The window keeps saved devices with per-host direction, one-click sync with live stage-by-stage progress and separate merge summaries for each machine, connection testing for first-time setup, cancellable runs while the app/stats server/playback is active, and manual database snapshots (create/merge/reveal/delete, stored in /tmp/subminer-db-snapshots/ by default). Hosts with auto-sync enabled sync in the background on a configurable interval, including during playback, with results reported as overlay notifications; hosts synced from the CLI are remembered in <config dir>/sync-hosts.json and appear in the window automatically.
• Merges are an insert-only union keyed on session UUIDs / video keys / series title keys, so re-syncing is idempotent and nothing is double-counted: each side snapshots its database (VACUUM INTO) from a consistent WAL point, snapshots are exchanged with scp, and each machine merges the other's data transactionally. Lifetime totals and daily/monthly rollups are updated incrementally (history older than the session retention window is preserved), unfinished sessions are excluded until a later sync sees them finalized, and remote-only historical rollups are copied only when they do not conflict with retained local session history. Sync aborts on stats schema version mismatches and refuses to run while the stats daemon or a live mpv session is active (--force overrides).
• The sync engine runs only inside the app: the sync window and the subminer sync command both delegate to SubMiner --sync-cli (headless, works over SSH with no display), so neither machine needs bun or the command-line launcher. A remote machine only needs SubMiner itself, found automatically as the app binary or via the launcher proxy.
• Windows remotes are supported: sync detects the remote shell (POSIX, cmd, or PowerShell) and manages remote temp files through SubMiner itself (sync --make-temp / --remove-temp) instead of mktemp / rm, so a Windows machine with the built-in OpenSSH Server works as a sync remote, found in its default Windows install location automatically.
• Added supporting flags: subminer sync <host> --check tests the SSH connection and remote launcher availability without syncing, subminer sync --snapshot <file> and --merge <file> expose the underlying steps for manual transfers, and subminer sync --json emits machine-readable NDJSON progress (the protocol the sync window consumes).