feat(sync-ui): defer app quit until async cleanup resolves

- check-host participates in active-run coordination and can be cancelled
- shutdown() cancels and awaits the active launcher run on quit
- onWillQuit calls preventDefault and re-triggers quit once cleanup settles
- Snapshot mode awaits tracker quiescent before writing output
- Auto-scheduler catches synchronous triggerHostSync failures
- SCP endpoint accepts Windows absolute paths; cmd.exe rejects % in quoted values
- runAppCommand unified (inherit vs pipe stdio) in launcher/mpv.ts
- Docs: add --check, --json, --ui, --sync-cli, --make-temp/--remove-temp examples

launcher/history-db.ts

@@ -6,6 +6,12 @@ import { resolveConfigDir } from '../src/config/path-resolution.js';
 import { readLauncherMainConfigObject } from './config/shared-config-reader.js';
 import type { HistoryVideoRow } from './history-types.js';
 import { resolvePathMaybe } from './util.js';
+import {
+  isReadonlyWalRetryError,
+  withReadonlyWalRetry,
+} from '../src/core/services/stats-sync/wal-retry.js';
+
+export { isReadonlyWalRetryError, withReadonlyWalRetry };
 
 export function resolveImmersionDbPath(): string {
   const root = readLauncherMainConfigObject();
@@ -43,12 +49,6 @@ export function queryLocalWatchHistory(dbPath: string): HistoryVideoRow[] {
   return withReadonlyWalRetry(dbPath, (options) => readHistoryRows(dbPath, options));
 }
 
-export {
-  withReadonlyWalRetry,
-  isReadonlyWalRetryError,
-} from '../src/core/services/stats-sync/wal-retry.js';
-import { withReadonlyWalRetry } from '../src/core/services/stats-sync/wal-retry.js';
-
 function tableExists(db: Database, tableName: string): boolean {
   return Boolean(
     db.query(`SELECT 1 FROM sqlite_master WHERE type = 'table' AND name = ?`).get(tableName),