feat(stats): wire stats server, overlay, and CLI into main process

- Stats server auto-start on immersion tracker init
- Stats overlay toggle via keybinding and IPC
- Stats CLI command (subminer stats) with cleanup mode
- mpv plugin menu integration for stats toggle
- CLI args for --stats, --stats-cleanup, --stats-response-path

src/main/runtime/initial-args-handler.ts

@@ -27,6 +27,7 @@ export function createHandleInitialArgsHandler(deps: {
     const mpvClient = deps.getMpvClient();
     if (
       !deps.isTexthookerOnlyMode() &&
+      !initialArgs.stats &&
       deps.hasImmersionTracker() &&
       mpvClient &&
       !mpvClient.connected