feat: 完成全量功能开发，包括前端管理后台与后端服务优化

此提交实现了完整的知识库管理系统：
1. 新增Vue3 + Antd Vue前端管理后台，包含登录、文档管理、检索、类目设置等完整页面
2. 重构后端LLM调用抽象层，支持Ollama与OpenAI兼容服务动态切换
3. 调整默认嵌入模型配置为本地bge-m3模式
4. 优化入库任务去重逻辑与缓存清理机制
5. 完善Docker镜像构建与docker-compose部署配置
6. 修复多项测试用例与兼容性问题
7. 新增运行时配置API，支持动态调整系统参数

app/api/v1/settings.py

@@ -0,0 +1,114 @@
+"""运行时配置 API：GET/PUT /api/v1/settings、GET /api/v1/settings/schema、POST /api/v1/settings/reset
+
+GET 任何登录用户可读；PUT/reset 需 admin。PUT 后会清空 LLM 客户端 / 解析插件 /
+去重策略三处进程级缓存，使新配置立即对后续请求生效。
+"""
+
+from typing import Any
+
+import structlog
+from fastapi import APIRouter, Depends
+from pydantic import BaseModel
+
+from app.api.response import ApiError, ok
+from app.core.auth import AuthUser, get_current_user, require_admin
+from app.core.dedup import invalidate_dedup_strategy_cache
+from app.core.file_parser import (
+    list_docx_plugins,
+    list_ocr_plugins,
+    list_pdf_plugins,
+    invalidate_parser_plugin_cache,
+)
+from app.core.runtime_settings import (
+    RuntimeSettings,
+    get_runtime_settings,
+    reset_runtime_settings,
+    update_runtime_settings,
+)
+from app.services.llm import invalidate_llm_client_cache
+
+logger = structlog.get_logger()
+
+router = APIRouter(prefix="/api/v1", tags=["settings"])
+
+
+class SettingsUpdateRequest(BaseModel):
+    """Settings PATCH body：任意子树可缺省，缺省字段保留原值
+
+    例：{"models": {"summarize": {"model": "qwen2.5:3b"}}}、
+        {"parsers": {"ocr": {"plugin": "tesseract"}}}、
+        {"dedup": {"strategy": "simhash", "simhash_threshold": 5}}
+    """
+
+    models: dict[str, Any] | None = None
+    parsers: dict[str, Any] | None = None
+    dedup: dict[str, Any] | None = None
+
+
+@router.get("/settings")
+async def get_settings(user: AuthUser = Depends(get_current_user)) -> dict[str, Any]:
+    """返回当前 RuntimeSettings（任何登录用户可读）"""
+    cfg = get_runtime_settings()
+    return ok(cfg.model_dump(mode="json"))
+
+
+@router.put("/settings")
+async def update_settings(
+    body: SettingsUpdateRequest,
+    user: AuthUser = Depends(require_admin),
+) -> dict[str, Any]:
+    """部分更新 RuntimeSettings（仅 admin）
+
+    更新成功后清空 LLM 客户端 / 解析插件 / 去重策略三处进程级缓存，
+    使新配置立即对后续请求生效。
+    """
+    patch = body.model_dump(exclude_none=True)
+    if not patch:
+        raise ApiError(1001, "请求体为空，未提供任何待更新字段")
+
+    try:
+        cfg = update_runtime_settings(patch)
+    except Exception as exc:
+        logger.error("RuntimeSettings 更新失败", error=str(exc), exc_info=True)
+        raise ApiError(2000, f"配置更新失败: {exc}") from exc
+
+    # 清缓存：让后续读取拿到新配置
+    invalidate_llm_client_cache()
+    invalidate_parser_plugin_cache()
+    invalidate_dedup_strategy_cache()
+    logger.info("RuntimeSettings 已更新并清理缓存", operator=user.username)
+    return ok(cfg.model_dump(mode="json"))
+
+
+@router.get("/settings/schema")
+async def get_settings_schema(
+    user: AuthUser = Depends(get_current_user),
+) -> dict[str, Any]:
+    """返回可选插件与策略列表（前端 Settings 页渲染选项用）"""
+    return ok(
+        {
+            "llm_providers": ["ollama", "openai_compatible"],
+            "pdf_plugins": list_pdf_plugins(),
+            "docx_plugins": list_docx_plugins(),
+            "ocr_plugins": list_ocr_plugins(),
+            "dedup_strategies": ["none", "sha256", "simhash"],
+        }
+    )
+
+
+@router.post("/settings/reset")
+async def reset_settings(
+    user: AuthUser = Depends(require_admin),
+) -> dict[str, Any]:
+    """重置 RuntimeSettings 为默认值（仅 admin），同时清缓存"""
+    try:
+        cfg = reset_runtime_settings()
+    except Exception as exc:
+        logger.error("RuntimeSettings 重置失败", error=str(exc), exc_info=True)
+        raise ApiError(2000, f"配置重置失败: {exc}") from exc
+
+    invalidate_llm_client_cache()
+    invalidate_parser_plugin_cache()
+    invalidate_dedup_strategy_cache()
+    logger.info("RuntimeSettings 已重置为默认值", operator=user.username)
+    return ok(cfg.model_dump(mode="json"))