feat: M4-02 — admin learning data views (sessions, AI analysis, AI usage logs)

- Add AdminLearningController with 3 endpoints:
  GET /admin-api/learning/sessions — learning sessions list
  GET /admin-api/learning/analysis — AI analysis results
  GET /admin-api/learning/ai-usage — AI usage logs

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/modules/learning-session/admin-learning.controller.ts

@@ -0,0 +1,100 @@
+import { Controller, Get, Query, UseGuards } from '@nestjs/common';
+import { ApiTags, ApiBearerAuth, ApiOperation, ApiQuery } from '@nestjs/swagger';
+import { PrismaService } from '../../infrastructure/database/prisma.service';
+import { AdminAuthGuard } from '../../common/guards/admin-auth.guard';
+import { AdminRolesGuard } from '../../common/guards/admin-roles.guard';
+
+@ApiTags('admin-learning')
+@ApiBearerAuth()
+@Controller('admin-api/learning')
+@UseGuards(AdminAuthGuard, AdminRolesGuard)
+export class AdminLearningController {
+  constructor(private readonly prisma: PrismaService) {}
+
+  @Get('sessions')
+  @ApiOperation({ summary: '学习会话列表' })
+  @ApiQuery({ name: 'userId', required: false })
+  @ApiQuery({ name: 'page', required: false })
+  @ApiQuery({ name: 'limit', required: false })
+  async listSessions(
+    @Query('userId') userId?: string,
+    @Query('page') page?: string,
+    @Query('limit') limit?: string,
+  ) {
+    const take = Math.min(Number(limit) || 20, 100);
+    const skip = (Math.max(Number(page) || 1, 1) - 1) * take;
+    const where: any = {};
+    if (userId) where.userId = userId;
+
+    const [items, total] = await Promise.all([
+      this.prisma.learningSession.findMany({
+        where,
+        orderBy: { startedAt: 'desc' },
+        take,
+        skip,
+        select: { id: true, userId: true, knowledgeBaseId: true, knowledgeItemId: true, mode: true, status: true, startedAt: true, endedAt: true, durationSeconds: true, focusMinutes: true },
+      }),
+      this.prisma.learningSession.count({ where }),
+    ]);
+    return { items, total };
+  }
+
+  @Get('analysis')
+  @ApiOperation({ summary: 'AI 分析结果列表' })
+  @ApiQuery({ name: 'userId', required: false })
+  @ApiQuery({ name: 'page', required: false })
+  @ApiQuery({ name: 'limit', required: false })
+  async listAnalysis(
+    @Query('userId') userId?: string,
+    @Query('page') page?: string,
+    @Query('limit') limit?: string,
+  ) {
+    const take = Math.min(Number(limit) || 20, 100);
+    const skip = (Math.max(Number(page) || 1, 1) - 1) * take;
+    const where: any = {};
+    if (userId) where.userId = userId;
+
+    const [items, total] = await Promise.all([
+      this.prisma.aiAnalysisResult.findMany({
+        where,
+        orderBy: { createdAt: 'desc' },
+        take,
+        skip,
+        select: { id: true, userId: true, jobId: true, summary: true, masteryScore: true, weaknesses: true, strengths: true, createdAt: true },
+      }),
+      this.prisma.aiAnalysisResult.count({ where }),
+    ]);
+    return { items, total };
+  }
+
+  @Get('ai-usage')
+  @ApiOperation({ summary: 'AI 调用日志' })
+  @ApiQuery({ name: 'userId', required: false })
+  @ApiQuery({ name: 'model', required: false })
+  @ApiQuery({ name: 'page', required: false })
+  @ApiQuery({ name: 'limit', required: false })
+  async listAiUsage(
+    @Query('userId') userId?: string,
+    @Query('model') model?: string,
+    @Query('page') page?: string,
+    @Query('limit') limit?: string,
+  ) {
+    const take = Math.min(Number(limit) || 20, 100);
+    const skip = (Math.max(Number(page) || 1, 1) - 1) * take;
+    const where: any = {};
+    if (userId) where.userId = userId;
+    if (model) where.model = { contains: model };
+
+    const [items, total] = await Promise.all([
+      this.prisma.aiUsageLog.findMany({
+        where,
+        orderBy: { createdAt: 'desc' },
+        take,
+        skip,
+        select: { id: true, userId: true, model: true, provider: true, inputTokens: true, outputTokens: true, estimatedCost: true, success: true, createdAt: true },
+      }),
+      this.prisma.aiUsageLog.count({ where }),
+    ]);
+    return { items, total };
+  }
+}

src/modules/learning-session/learning-session.module.ts

@@ -1,10 +1,11 @@
 import { Module } from '@nestjs/common';
 import { LearningSessionController } from './learning-session.controller';
+import { AdminLearningController } from './admin-learning.controller';
 import { LearningSessionService } from './learning-session.service';
 import { LearningSessionRepository } from './learning-session.repository';
 
 @Module({
-  controllers: [LearningSessionController],
+  controllers: [LearningSessionController, AdminLearningController],
   providers: [LearningSessionService, LearningSessionRepository],
   exports: [LearningSessionService],
 })