Phase 1 scaffold: auth for all apps

- Backend: Fastify with two listeners (public + internal), routes, services, DB migration + seed
- client_app: Flutter with BLoC, all auth screens (welcome, display name, register, OTP, force-register)
- mitra_app: Flutter with BLoC, OTP-only login
- control_center: React + Vite, email/password login, mitra/user management, anonymity settings
- Docs: phase1 plan, API contract, client app mockup
- CLAUDE.md and shared memory for all subprojects

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/src/routes/public/client.auth.routes.js

@@ -0,0 +1,15 @@
+import { authenticate } from '../../plugins/auth.js'
+import { getCustomerByFirebaseUid } from '../../services/customer.service.js'
+
+export const clientAuthRoutes = async (app) => {
+  app.post('/verify', { preHandler: authenticate }, async (request, reply) => {
+    const customer = await getCustomerByFirebaseUid(request.firebaseUser.uid)
+    if (!customer) {
+      return reply.code(404).send({
+        success: false,
+        error: { code: 'NOT_FOUND', message: 'Customer account not found' },
+      })
+    }
+    return reply.send({ success: true, data: customer })
+  })
+}