feat(desktop): two-way cloud sync with mobile and web

Rewrites the desktop mirror as services/sync/SyncEngine: a persistent
outbox, per-account server-clock keyset cursors with paging, pulls that never
overwrite unsent local edits, deletions both ways through sync_tombstones and
per-row failure isolation. It now covers history titles and favorites,
dictionary, every meeting's memos and documents, memo tags, user commands and
dictation/meeting templates, and registers the desktop as a device that the
phone can disconnect.

Fixes shipped defects: the first pull after sign-in fetched nothing, only
the first meeting's children were pushed, team meetings leaked into the
personal database and lost team_id on re-push, and Realtime never connected
because Electron's Node 20 has no global WebSocket (ws is now the transport).
Anonymous local-mode records are imported into the first account that signs
in. The settings sync section is translated and shows pending/rejected
changes; synced screens reload on app:dataChanged.

apps/desktop/package.json

@@ -34,6 +34,7 @@
     "@types/node": "^22.13.0",
     "@types/react": "^19.0.0",
     "@types/react-dom": "^19.0.0",
+    "@types/ws": "^8.18.1",
     "@vitejs/plugin-react": "^4.3.0",
     "electron": "33.4.11",
     "electron-builder": "^26.8.1",
@@ -67,7 +68,8 @@
     "react-markdown": "^10.1.0",
     "remark-gfm": "^4.0.1",
     "tar": "^7.5.13",
-    "uiohook-napi": "^1.5.5"
+    "uiohook-napi": "^1.5.5",
+    "ws": "^8.22.0"
   },
   "optionalDependencies": {
     "@rollup/rollup-win32-x64-msvc": "^4.60.1"