✨ feat(admin): add user data dashboard for cross-project data visualization

Add comprehensive admin dashboard to view and manage user data across all projects:

Backend:
- Add admin endpoints to Chat, Todo, Contacts, Calendar, Picture, Zitare, Presi
- Each backend exposes GET/DELETE /api/v1/admin/user-data/:userId
- Service-to-service auth via X-Service-Key header

Aggregation (mana-core-auth):
- GET /api/v1/admin/users - Paginated user list with search
- GET /api/v1/admin/users/:userId/data - Aggregated data from all backends
- DELETE /api/v1/admin/users/:userId/data - GDPR deletion across all projects

Frontend (ManaCore web):
- New User Data tab in admin navigation
- User search page at /admin/user-data
- User detail page with ProjectDataCard components
- GDPR deletion dialog with email confirmation

Presi:
- Migrate user_id from UUID to TEXT for Better Auth compatibility
- Add SQL migration script

apps/zitare/apps/backend/src/admin/admin.controller.ts

@@ -0,0 +1,34 @@
+import {
+	Controller,
+	Get,
+	Delete,
+	Param,
+	UseGuards,
+	Logger,
+	HttpCode,
+	HttpStatus,
+} from '@nestjs/common';
+import { AdminService } from './admin.service';
+import { ServiceAuthGuard } from './guards/service-auth.guard';
+import { UserDataResponse, DeleteUserDataResponse } from './dto/user-data-response.dto';
+
+@Controller('api/v1/admin')
+@UseGuards(ServiceAuthGuard)
+export class AdminController {
+	private readonly logger = new Logger(AdminController.name);
+
+	constructor(private readonly adminService: AdminService) {}
+
+	@Get('user-data/:userId')
+	async getUserData(@Param('userId') userId: string): Promise<UserDataResponse> {
+		this.logger.log(`Admin request: getUserData for userId=${userId}`);
+		return this.adminService.getUserData(userId);
+	}
+
+	@Delete('user-data/:userId')
+	@HttpCode(HttpStatus.OK)
+	async deleteUserData(@Param('userId') userId: string): Promise<DeleteUserDataResponse> {
+		this.logger.log(`Admin request: deleteUserData for userId=${userId}`);
+		return this.adminService.deleteUserData(userId);
+	}
+}

apps/zitare/apps/backend/src/admin/admin.module.ts

@@ -0,0 +1,12 @@
+import { Module } from '@nestjs/common';
+import { ConfigModule } from '@nestjs/config';
+import { AdminController } from './admin.controller';
+import { AdminService } from './admin.service';
+import { DatabaseModule } from '../db/database.module';
+
+@Module({
+	imports: [ConfigModule, DatabaseModule],
+	controllers: [AdminController],
+	providers: [AdminService],
+})
+export class AdminModule {}

apps/zitare/apps/backend/src/admin/admin.service.ts

@@ -0,0 +1,87 @@
+import { Injectable, Logger } from '@nestjs/common';
+import { Inject } from '@nestjs/common';
+import { NodePgDatabase } from 'drizzle-orm/node-postgres';
+import { eq, sql, desc } from 'drizzle-orm';
+import * as schema from '../db/schema';
+import {
+	UserDataResponse,
+	DeleteUserDataResponse,
+	EntityCount,
+} from './dto/user-data-response.dto';
+
+@Injectable()
+export class AdminService {
+	private readonly logger = new Logger(AdminService.name);
+
+	constructor(
+		@Inject('DATABASE_CONNECTION')
+		private readonly db: NodePgDatabase<typeof schema>
+	) {}
+
+	async getUserData(userId: string): Promise<UserDataResponse> {
+		this.logger.log(`Getting user data for userId: ${userId}`);
+
+		// Count favorites
+		const favoritesResult = await this.db
+			.select({ count: sql<number>`count(*)::int` })
+			.from(schema.favorites)
+			.where(eq(schema.favorites.userId, userId));
+		const favoritesCount = favoritesResult[0]?.count ?? 0;
+
+		// Count user lists
+		const userListsResult = await this.db
+			.select({ count: sql<number>`count(*)::int` })
+			.from(schema.userLists)
+			.where(eq(schema.userLists.userId, userId));
+		const userListsCount = userListsResult[0]?.count ?? 0;
+
+		// Get last activity
+		const lastFavorite = await this.db
+			.select({ createdAt: schema.favorites.createdAt })
+			.from(schema.favorites)
+			.where(eq(schema.favorites.userId, userId))
+			.orderBy(desc(schema.favorites.createdAt))
+			.limit(1);
+		const lastActivityAt = lastFavorite[0]?.createdAt?.toISOString();
+
+		const entities: EntityCount[] = [
+			{ entity: 'favorites', count: favoritesCount, label: 'Favorites' },
+			{ entity: 'user_lists', count: userListsCount, label: 'User Lists' },
+		];
+
+		const totalCount = favoritesCount + userListsCount;
+
+		return { entities, totalCount, lastActivityAt };
+	}
+
+	async deleteUserData(userId: string): Promise<DeleteUserDataResponse> {
+		this.logger.log(`Deleting user data for userId: ${userId}`);
+
+		const deletedCounts: EntityCount[] = [];
+		let totalDeleted = 0;
+
+		// Delete favorites
+		const deletedFavorites = await this.db
+			.delete(schema.favorites)
+			.where(eq(schema.favorites.userId, userId))
+			.returning();
+		deletedCounts.push({ entity: 'favorites', count: deletedFavorites.length, label: 'Favorites' });
+		totalDeleted += deletedFavorites.length;
+
+		// Delete user lists
+		const deletedUserLists = await this.db
+			.delete(schema.userLists)
+			.where(eq(schema.userLists.userId, userId))
+			.returning();
+		deletedCounts.push({
+			entity: 'user_lists',
+			count: deletedUserLists.length,
+			label: 'User Lists',
+		});
+		totalDeleted += deletedUserLists.length;
+
+		this.logger.log(`Deleted ${totalDeleted} records for userId: ${userId}`);
+
+		return { success: true, deletedCounts, totalDeleted };
+	}
+}

apps/zitare/apps/backend/src/admin/dto/user-data-response.dto.ts

@@ -0,0 +1,17 @@
+export interface EntityCount {
+	entity: string;
+	count: number;
+	label: string;
+}
+
+export interface UserDataResponse {
+	entities: EntityCount[];
+	totalCount: number;
+	lastActivityAt?: string;
+}
+
+export interface DeleteUserDataResponse {
+	success: boolean;
+	deletedCounts: EntityCount[];
+	totalDeleted: number;
+}

apps/zitare/apps/backend/src/admin/guards/service-auth.guard.ts

@@ -0,0 +1,36 @@
+import {
+	Injectable,
+	CanActivate,
+	ExecutionContext,
+	UnauthorizedException,
+	Logger,
+} from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import { Request } from 'express';
+
+@Injectable()
+export class ServiceAuthGuard implements CanActivate {
+	private readonly logger = new Logger(ServiceAuthGuard.name);
+	private readonly serviceKey: string;
+
+	constructor(private readonly configService: ConfigService) {
+		this.serviceKey = this.configService.get<string>('ADMIN_SERVICE_KEY', 'dev-admin-key');
+	}
+
+	canActivate(context: ExecutionContext): boolean {
+		const request = context.switchToHttp().getRequest<Request>();
+		const providedKey = request.headers['x-service-key'] as string;
+
+		if (!providedKey) {
+			this.logger.warn('Missing X-Service-Key header');
+			throw new UnauthorizedException('Missing service key');
+		}
+
+		if (providedKey !== this.serviceKey) {
+			this.logger.warn('Invalid service key provided');
+			throw new UnauthorizedException('Invalid service key');
+		}
+
+		return true;
+	}
+}

apps/zitare/apps/backend/src/app.module.ts

@@ -4,6 +4,7 @@ import { DatabaseModule } from './db/database.module';
 import { FavoriteModule } from './favorite/favorite.module';
 import { ListModule } from './list/list.module';
 import { HealthModule } from '@manacore/shared-nestjs-health';
+import { AdminModule } from './admin/admin.module';
 
 @Module({
 	imports: [
@@ -15,6 +16,7 @@ import { HealthModule } from '@manacore/shared-nestjs-health';
 		FavoriteModule,
 		ListModule,
 		HealthModule.forRoot({ serviceName: 'quote-backend' }),
+		AdminModule,
 	],
 })
 export class AppModule {}