feat: TTS服务 + 数字人面试组件 (P1)

backend/src/modules/interview/interview.controller.ts

@@ -28,7 +28,9 @@ export class InterviewController {
     @Param('id') id: string,
     @CurrentUser('userId') userId: string,
     @Body('answer') answer: string,
+    @Body('avatar') avatar?: boolean,
   ) {
+    if (avatar) return this.interviewService.answerWithAvatar(id, userId, answer)
     return this.interviewService.answer(id, userId, answer)
   }
 

backend/src/modules/interview/interview.module.ts

@@ -5,6 +5,7 @@ import { InterviewService } from './interview.service'
 import { Interview, InterviewSchema } from './interview.schema'
 import { Progress, ProgressSchema } from '../schemas/progress.schema'
 import { UserModule } from '../user/user.module'
+import { TtsModule } from '../tts/tts.module'
 
 @Module({
   imports: [
@@ -13,6 +14,7 @@ import { UserModule } from '../user/user.module'
       { name: Progress.name, schema: ProgressSchema },
     ]),
     UserModule,
+    TtsModule,
   ],
   controllers: [InterviewController],
   providers: [InterviewService],

backend/src/modules/interview/interview.service.ts

@@ -6,6 +6,7 @@ import { Progress, ProgressDocument } from '../schemas/progress.schema'
 import { AiService } from '../ai/ai.service'
 import { UserService } from '../user/user.service'
 import { QuotaService } from '../user/quota.service'
+import { TtsService } from '../tts/tts.service'
 import { analyzeSpeech } from '../../common/utils/filler-words'
 
 @Injectable()
@@ -16,6 +17,7 @@ export class InterviewService {
     private aiService: AiService,
     private userService: UserService,
     private quotaService: QuotaService,
+    private ttsService: TtsService,
   ) {}
 
   async create(userId: string, position: string) {
@@ -99,6 +101,20 @@ ${conversationHistory}
     }
   }
 
+  async answerWithAvatar(interviewId: string, userId: string, answer: string) {
+    const base = await this.answer(interviewId, userId, answer)
+    const aiMsg = base.messages?.find(m => m.role === 'ai')
+    if (aiMsg?.content) {
+      try {
+        const tts = await this.ttsService.synthesize(aiMsg.content)
+        return { ...base, ttsHash: tts.hash, ttsDurationMs: tts.durationMs }
+      } catch {
+        // TTS failure is non-critical, return without audio
+      }
+    }
+    return base
+  }
+
   async complete(interviewId: string, userId: string) {
     const interview = await this.interviewModel.findOne({ _id: interviewId, userId }).exec()
     if (!interview) throw new HttpException('面试不存在', HttpStatus.NOT_FOUND)