feat: 新增多格式文件上传入库与认证体系

- 新增 JWT 认证模块，支持登录/注册/用户管理
- 新增文件上传接口，支持 .txt/.md/.html/.pdf/.docx 等格式解析入库
- 新增检索结果 AI 总结功能
- 新增文本去重缓存机制
- 新增全局认证夹具简化测试
- 新增配置项与环境变量支持
- 完善文档与测试覆盖

app/api/v1/knowledge.py

@@ -4,10 +4,11 @@ from functools import lru_cache
 from typing import Any
 
 import structlog
-from fastapi import APIRouter
+from fastapi import APIRouter, Depends
 
 from app.api.response import ApiError, ok
 from app.config import settings
+from app.core.auth import AuthUser, get_current_user
 from app.models.knowledge import UNCATEGORIZED, TaxonomyCategory, load_taxonomy
 from app.services.qdrant import ALL_COLLECTIONS, COLLECTION_L1, QdrantService
 
@@ -36,14 +37,14 @@ def _get_taxonomy() -> list[TaxonomyCategory]:
 
 
 @router.get("/knowledge/categories")
-async def list_categories() -> dict[str, Any]:
+async def list_categories(user: AuthUser = Depends(get_current_user)) -> dict[str, Any]:
     """返回完整知识分类类目集"""
     categories = _get_taxonomy()
     return ok({"categories": [c.model_dump() for c in categories], "count": len(categories)})
 
 
 @router.get("/knowledge/stats")
-async def knowledge_stats() -> dict[str, Any]:
+async def knowledge_stats(user: AuthUser = Depends(get_current_user)) -> dict[str, Any]:
     """返回四层集合规模与 L1 类目分布统计"""
     service = _get_qdrant()
     try: