AppForge: migrate off Supabase to external Postgres + Better Auth + local storage

- New Express + TypeScript backend (server/) with pg, Better Auth, local file storage
- De-Supabased Postgres schema (server/db) and TS reimplementations of DB functions
- Frontend data layer rewired to REST (rest-client + backend-client compat shim)
- Removed all Supabase references (code, config, deps, docs)
- New brand assets: gradient favicon/app icons + dark/white wordmark logos

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

capacitor.config.ts

@@ -0,0 +1,13 @@
+import type { CapacitorConfig } from '@capacitor/cli';
+
+const config: CapacitorConfig = {
+  appId: 'com.app.appforge',
+  appName: 'AppForge',
+  webDir: 'dist',
+  server: {
+    url: 'https://61c63823-3472-48e3-a148-faed88715111.lovableproject.com?forceHideBadge=true',
+    cleartext: true
+  }
+};
+
+export default config;