docs & cleanup: update stack info, remove dead code, fix backend bugs

- Fix AGENTS.md and 技术架构设计.md to reflect actual stack (Prisma+MySQL, static export, PM2)
- Remove 4 unused frontend components (page-transition, page-layout, image-upload, section-card)
- Fix card.tsx hardcoded colors → CSS variables
- Remove provider name from model selector, remove sensenova-u1-fast from models
- Fix analytics.controller.ts raw SQL table names (runtime bug)
- Add JWT auth guard to tools POST endpoint
- Fix AI gateway test: update env vars and model names
- Fix admin test: mock role structure for Prisma relation

backend/src/modules/tools/tools.controller.ts

@@ -1,5 +1,6 @@
-import { Controller, Get, Post, Body, Query } from '@nestjs/common';
-import { ApiTags } from '@nestjs/swagger';
+import { Controller, Get, Post, Body, Query, UseGuards } from '@nestjs/common';
+import { ApiTags, ApiBearerAuth } from '@nestjs/swagger';
+import { AuthGuard } from '@nestjs/passport';
 import { ToolsService } from './tools.service';
 
 @ApiTags('AI工具')
@@ -13,6 +14,8 @@ export class ToolsController {
   }
 
   @Post()
+  @UseGuards(AuthGuard('jwt'))
+  @ApiBearerAuth()
   async create(@Body() body: { name: string; description?: string; url: string; icon?: string; categoryId?: number; tags?: string }) {
     return this.toolsService.create(body);
   }