feat: OpenMesh 基础平台与 MD/PDF 转换技能

- 后端: coworker 智能体框架, WS API, 文件上传, 附件处理
- 前端: Open WebUI, 文件全量走 upload API (含 MD/TXT/JSON 等文本类)
- 技能: md-to-office (pandoc + wkhtmltopdf)
- 修复: 上传文件路径丢失, Agent 搜索浪费, 输出文件跑到 uploads/
- 打包: PyInstaller one-dir, 预打包 pandoc/wkhtmltopdf/chromium

coworker/mcp/__init__.py

@@ -0,0 +1,29 @@
+"""MCP integration — our own async client on the official `mcp` SDK.
+
+Public API: config loading/mutation, the connection manager, and tool wrapping.
+"""
+
+from __future__ import annotations
+
+from .client import MCPManager
+from .config import (
+    MCPServerDef,
+    delete_global_server,
+    load_mcp_servers,
+    patch_global_server,
+    put_global_server,
+    read_global,
+)
+from .tools import build_callables, tool_name
+
+__all__ = [
+    "MCPManager",
+    "MCPServerDef",
+    "load_mcp_servers",
+    "read_global",
+    "put_global_server",
+    "patch_global_server",
+    "delete_global_server",
+    "build_callables",
+    "tool_name",
+]