feat(frontend): TypeScript-Monorepo mit Terminal-UI für Effigenix ERP

Monorepo-Setup (pnpm workspaces) mit vier shared Packages und einer TUI-App:

Shared Packages:
- @effigenix/types: TypeScript-DTOs (UserDTO, RoleDTO, AuthDTO, Enums)
- @effigenix/config: API-Konfiguration und Shared Constants
- @effigenix/validation: Zod-Schemas für Username, E-Mail und Passwort
- @effigenix/api-client: axios-Client mit JWT-Handling (proaktiver + reaktiver
  Token-Refresh), AuthInterceptor, ErrorInterceptor, Resources für auth/users/roles

TUI (apps/cli, Ink 5 / React):
- Authentication: Login/Logout, Session-Restore beim Start, JWT-Refresh
- User Management: Liste, Anlage (Zod-Inline-Validation), Detailansicht,
  Passwort ändern, Sperren/Entsperren mit ConfirmDialog
- Role Management: Liste, Detailansicht, Zuweisen/Entfernen per RoleSelectList (↑↓)
- UX: SuccessDisplay (Auto-Dismiss 3 s), ConfirmDialog (J/N),
  FormInput mit Inline-Fehlern, StatusBar mit API-URL
- Layout: Fullscreen-Modus (alternate screen buffer), Header mit eingeloggtem User
- Tests: vitest + ink-testing-library (15 Tests)

frontend/apps/cli/src/index.tsx

@@ -0,0 +1,24 @@
+import React from 'react';
+import { render } from 'ink';
+import { App } from './App.js';
+
+// Alternate screen buffer + clear + hide cursor
+process.stdout.write('\x1b[?1049h\x1b[2J\x1b[H\x1b[?25l');
+
+const cleanup = () => {
+  process.stdout.write('\x1b[?25h\x1b[?1049l');
+};
+
+process.on('exit', cleanup);
+process.on('SIGINT', () => {
+  cleanup();
+  process.exit(0);
+});
+process.on('SIGTERM', () => {
+  cleanup();
+  process.exit(0);
+});
+
+const { waitUntilExit } = render(<App />);
+
+waitUntilExit().then(cleanup).catch(cleanup);