refactor: 移除模板迁移API接口，改为migrations阶段处理

- 删除 template-migration.service.ts 文件
- 移除控制器中的迁移相关API接口 (/migrate, /sync, /admin/migration-report)
- 清理文档中的迁移服务相关内容
- 添加 data-source.ts 配置文件用于运行数据库迁移
- 模板迁移功能完全通过数据库migration脚本处理

docs/template-hybrid-architecture.md

@@ -7,6 +7,7 @@
 - **代码层**：抽象类定义执行逻辑和接口规范
 - **数据库层**：存储具体模板的配置信息
 - **Entity层**：动态从数据库加载配置，创建模板实例
+- **Migration层**：通过数据库迁移脚本初始化模板配置数据
 
 ## 🏗️ 架构层次分析
 
@@ -373,18 +374,8 @@ export class TemplateController {
     @Param('templateId', ParseIntPipe) templateId: number,
     @Body() { imageUrl }: { imageUrl: string }
   ) {
-    // 动态创建模板实例并执行
-    const config = await this.templateFactory.templateRepository.findOne({
-      where: { id: templateId }
-    });
-
-    let template;
-    if (config.templateType === TemplateType.IMAGE) {
-      template = await this.templateFactory.createImageTemplate(templateId);
-    } else {
-      template = await this.templateFactory.createVideoTemplate(templateId);
-    }
-
+    // 通过工厂服务创建模板实例并执行
+    const template = await this.templateFactory.createTemplate(templateId);
     return await template.execute(imageUrl);
   }
 
@@ -395,83 +386,16 @@ export class TemplateController {
 
   @Get('image')
   async getImageTemplates() {
-    return this.templateFactory.getTemplatesByType(TemplateType.IMAGE);
+    return this.templateFactory.getImageTemplates();
   }
 
   @Get('video') 
   async getVideoTemplates() {
-    return this.templateFactory.getTemplatesByType(TemplateType.VIDEO);
+    return this.templateFactory.getVideoTemplates();
   }
 }
 ```
 
-### 3. 数据迁移脚本
-```typescript
-// 将现有代码中的模板配置迁移到数据库
-// src/migrations/migrate-templates.ts
-import { Injectable } from '@nestjs/common';
-import { InjectRepository } from '@nestjs/typeorm';
-import { Repository } from 'typeorm';
-import { N8nTemplateEntity, TemplateType } from '../entities/n8n-template.entity';
-
-// 导入现有模板
-import { PhotoRestoreTemplate } from '../templates/n8nTemplates/PhotoRestoreTemplate';
-import { CharacterFigurineTemplate } from '../templates/n8nTemplates/CharacterFigurineTemplate';
-
-@Injectable()
-export class TemplateMigrationService {
-  constructor(
-    @InjectRepository(N8nTemplateEntity)
-    private templateRepository: Repository<N8nTemplateEntity>,
-  ) {}
-
-  async migrateExistingTemplates() {
-    // 迁移现有模板配置
-    const templates = [
-      new PhotoRestoreTemplate(),
-      new CharacterFigurineTemplate(),
-      // ... 其他模板
-    ];
-
-    for (const template of templates) {
-      const existing = await this.templateRepository.findOne({
-        where: { code: template.code }
-      });
-
-      if (!existing) {
-        const entity = new N8nTemplateEntity();
-        entity.code = template.code;
-        entity.name = template.name;
-        entity.description = template.description;
-        entity.creditCost = template.creditCost;
-        entity.version = template.version;
-        entity.inputExampleUrl = template.input;
-        entity.outputExampleUrl = template.output;
-        entity.tags = template.tags;
-
-        // 判断模板类型
-        if (template instanceof N8nImageGenerateTemplate) {
-          entity.templateType = TemplateType.IMAGE;
-          entity.imageModel = template.imageModel;
-          entity.imagePrompt = template.imagePrompt;
-        } else if (template instanceof N8nVideoGenerateTemplate) {
-          entity.templateType = TemplateType.VIDEO;
-          entity.imageModel = template.imageModel;
-          entity.imagePrompt = template.imagePrompt;
-          entity.videoModel = template.videoModel;
-          entity.videoPrompt = template.videoPrompt;
-          entity.duration = template.duration;
-          entity.aspectRatio = template.aspectRatio;
-        }
-
-        entity.templateClass = template.constructor.name;
-        
-        await this.templateRepository.save(entity);
-      }
-    }
-  }
-}
-```
 
 ## ✅ 架构优势