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

frontend/src/lib/models.ts

@@ -6,10 +6,9 @@ export interface ModelOption {
 }
 
 export const AVAILABLE_MODELS: ModelOption[] = [
-  { id: 'general', label: '通用模式', provider: 'OpenAI 兼容', desc: '日常问答，综合能力均衡' },
-  { id: 'deepseek-v4-flash', label: 'DeepSeek V4 Flash', provider: '商汤科技', desc: '高速推理，代码生成强' },
-  { id: 'sensenova-6.7-flash-lite', label: 'SenseNova 6.7 Flash Lite', provider: '商汤科技', desc: '轻量快速，日常使用' },
-  { id: 'sensenova-u1-fast', label: 'SenseNova U1 Fast', provider: '商汤科技', desc: '高性能推理，复杂任务' },
+  { id: 'general', label: '通用模式', provider: '', desc: '日常问答，综合能力均衡' },
+  { id: 'deepseek-v4-flash', label: 'DeepSeek V4 Flash', provider: '', desc: '高速推理，代码生成强' },
+  { id: 'sensenova-6.7-flash-lite', label: 'SenseNova 6.7 Flash Lite', provider: '', desc: '轻量快速，日常使用' },
 ];
 
 export const DEFAULT_MODEL = 'general';