feat(db): migrate from lowdb to SQLite with repos pattern

- Add modular DB layer (adapters, migrations, repos, helpers)
- Replace localDb/usageDb/requestDetailsDb monoliths with repos
- Add Tailscale tunnel integration & status check API
- Add /api/cli-tools/all-statuses aggregated endpoint
- Add settingsStore (Zustand) and mitm/dbReader
- Add DB unit tests (benchmark, concurrent, migration, vs-lowdb)

src/app/api/cli-tools/antigravity-mitm/route.js

@@ -16,7 +16,7 @@ import { getSettings, updateSettings } from "@/lib/localDb";
 
 initDbHooks(getSettings, updateSettings);
 
-const DEFAULT_MITM_ROUTER_BASE = "http://localhost:20128";
+const DEFAULT_MITM_ROUTER_BASE = "http://127.0.0.1:20128";
 
 function normalizeMitmRouterBaseUrlInput(input) {
   if (input == null || String(input).trim() === "") {