feat: complete admin panel and backend admin api migration

apps/api/src/modules/auth/auth.controller.ts

@@ -0,0 +1,31 @@
+import { Body, Controller, Get, HttpCode, Post } from '@nestjs/common';
+import { AuthService } from './auth.service';
+import { LoginDto } from './dto/login.dto';
+import { CurrentAdmin, Public } from './guards';
+import type { AuthenticatedAdmin } from './jwt.strategy';
+
+/**
+ * Legacy endpoints (henza_server routes/admin.php):
+ *   POST admin-login  -> AdminController::login
+ *   GET  users/show   -> UserController::showData
+ *
+ * Exposed here under the clean /api/admin/auth prefix; the admin panel's mapping
+ * layer translates the legacy paths onto these.
+ */
+@Controller('admin/auth')
+export class AuthController {
+  constructor(private readonly authService: AuthService) {}
+
+  @Public()
+  @Post('login')
+  @HttpCode(200)
+  login(@Body() dto: LoginDto) {
+    return this.authService.login(dto);
+  }
+
+  /** Legacy `users/show` — the router guard's permission refresh. */
+  @Get('me')
+  me(@CurrentAdmin() admin: AuthenticatedAdmin) {
+    return this.authService.showData(admin.id);
+  }
+}