init: RAG 知识库服务初始提交

- 后端 API（Flask + Gunicorn）
- RAG 引擎（混合检索 + 云端 Reranker + 引用溯源）
- 文档解析（MinerU + 多格式支持）
- Docker 生产部署配置
- 排除前端项目、敏感配置、模型文件

api/session_routes.py

@@ -0,0 +1,114 @@
+"""
+会话管理 API
+
+路由:
+- GET    /sessions              - 用户会话列表
+- GET    /history/<session_id>  - 获取会话历史
+- DELETE /session/<session_id>  - 删除会话
+- POST   /clear/<session_id>   - 清空会话历史
+"""
+
+from flask import Blueprint, request, jsonify, current_app
+from auth.gateway import require_gateway_auth
+
+session_bp = Blueprint('session', __name__)
+
+
+@session_bp.route('/sessions', methods=['GET'])
+@require_gateway_auth
+def get_sessions():
+    """
+    获取用户的会话列表
+
+    返回:
+    {
+        "sessions": [
+            {
+                "session_id": "...",
+                "created_at": "...",
+                "last_active": "...",
+                "preview": "最后一条消息预览..."
+            }
+        ]
+    }
+    """
+    session_manager = current_app.config['SESSION_MANAGER']
+    user_id = request.current_user["user_id"]
+
+    sessions = session_manager.get_user_sessions(user_id, limit=20)
+
+    # 添加最后一条消息预览
+    for s in sessions:
+        history = session_manager.get_history(s["session_id"], limit=1)
+        if history:
+            s["preview"] = history[0]["content"][:50] + "..."
+        else:
+            s["preview"] = "空会话"
+
+    return jsonify({"sessions": sessions})
+
+
+@session_bp.route('/history/<session_id>', methods=['GET'])
+@require_gateway_auth
+def get_history(session_id):
+    """
+    获取会话历史
+
+    返回:
+    {
+        "history": [
+            {"role": "user/assistant", "content": "...", "created_at": "..."}
+        ]
+    }
+    """
+    session_manager = current_app.config['SESSION_MANAGER']
+    user_id = request.current_user["user_id"]
+
+    # 验证会话归属
+    sessions = session_manager.get_user_sessions(user_id)
+    session_ids = [s["session_id"] for s in sessions]
+
+    if session_id not in session_ids:
+        return jsonify({"error": "无权访问此会话"}), 403
+
+    history = session_manager.get_history(session_id, limit=100)
+
+    return jsonify({"history": history})
+
+
+@session_bp.route('/session/<session_id>', methods=['DELETE'])
+@require_gateway_auth
+def delete_session(session_id):
+    """删除会话"""
+    session_manager = current_app.config['SESSION_MANAGER']
+    user_id = request.current_user["user_id"]
+
+    # 验证会话归属
+    sessions = session_manager.get_user_sessions(user_id)
+    session_ids = [s["session_id"] for s in sessions]
+
+    if session_id not in session_ids:
+        return jsonify({"error": "无权删除此会话"}), 403
+
+    session_manager.delete_session(session_id)
+
+    return jsonify({"success": True, "message": "会话已删除"})
+
+
+@session_bp.route('/clear/<session_id>', methods=['POST'])
+@require_gateway_auth
+def clear_history(session_id):
+    """清空会话历史（保留会话）"""
+    session_manager = current_app.config['SESSION_MANAGER']
+    user_id = request.current_user["user_id"]
+
+    # 验证会话归属
+    sessions = session_manager.get_user_sessions(user_id)
+    session_ids = [s["session_id"] for s in sessions]
+
+    if session_id not in session_ids:
+        return jsonify({"error": "无权操作此会话"}), 403
+
+    session_manager.clear_history(session_id)
+
+    return jsonify({"success": True, "message": "历史已清空"})