fix(mcp): surface BaseExceptionGroup from add_tool_server connect

[openjiuwen-sync-bot]

Paired: GitHub #443 ↔ GitCode !2260

Summary

Fixes #​1497: MCP server connection failures wrapped in an exception group were silently swallowed by ToolMgr.add_tool_server, and task cancellation was broken.

Root cause

asyncio.CancelledError and BaseExceptionGroup both inherit from BaseException, NOT Exception. The old handler was a bare:

except Exception as e:
    raise build_error(StatusCode.RESOURCE_MCP_SERVER_ADD_ERROR, ...) from e

So a connection failure raised inside asyncio.gather/TaskGroup (wrapped in a BaseExceptionGroup) escaped the handler entirely and propagated as an untyped error instead of the proper RESOURCE_MCP_SERVER_ADD_ERROR (110512). Similarly, CancelledError escaping mid-connect could not be distinguished from a real failure.

Change (openjiuwen/core/runner/resources_manager/tool_manager.py)

1. except asyncio.CancelledError: raise — task cancellation now propagates correctly instead of being mis-wrapped into a business error (cooperative cancellation preserved).
2. except BaseExceptionGroup as e — group-wrapped failures now become RESOURCE_MCP_SERVER_ADD_ERROR. A single-exception group (the common asyncio.gather case) is unwrapped so the real cause (RuntimeError("boom")) appears in the error message instead of the unhelpful "… (1 sub-exception)".
3. except Exception remains for ordinary failures (unchanged behavior).

Tests (tests/unit_tests/core/runner/test_tool_manager_mcp_exception.py, new)

• BaseExceptionGroup from connect() → WorkflowError with code 110512 and the inner cause surfaced
• asyncio.CancelledError from connect() → propagates unwrapped
• plain ConnectionError → still wrapped as 110512 (regression guard)

Verification

• Windows (Python 3.12 + uv): uv run pytest tests/unit_tests/core/runner/test_tool_manager_mcp_exception.py — 3 passed
• Linux (Docker, python:3.12-slim + uv): same command — 3 passed

Linked Closing Issues:

• Fixes [Bug] MCP server 连接失败被静默吞掉:add_tool_server 的 except Exception 无法捕获 CancelledError / BaseExceptionGroup #414

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[openjiuwen-collaboration-bot]

head_sha: ff698d8f1d405b346ba56ed788edda81b5ce538c

⚠️ 本次变更过大（1296 个可审文件、252713 行），已超出 AI 代码评审的处理范围，本次跳过。建议拆分为更小的 PR 以获得有效评审。

[openjiuwen-collaboration-bot]

head_sha: ff698d8f1d405b346ba56ed788edda81b5ce538c

⚠️ 本次变更过大（1296 个可审文件、252713 行），已超出 AI 代码评审的处理范围，本次跳过。建议拆分为更小的 PR 以获得有效评审。

[openjiuwen-collaboration-bot]

head_sha: ff698d8f1d405b346ba56ed788edda81b5ce538c

任务名称	结果	日志操作
静态检查	✅SUCCESS	点此跳转
防投毒检查	✅SUCCESS	点此跳转
开源合规检查	✅SUCCESS	点此跳转
UT测试	✅SUCCESS	点此跳转
ST测试	N/A	N/A
build 编译包	N/A	N/A
ruff codecheck	✅SUCCESS	N/A

[openjiuwen-collaboration-bot]

head_sha: ff698d8f1d405b346ba56ed788edda81b5ce538c

任务名称	结果	日志操作
静态检查	✅SUCCESS	点此跳转
防投毒检查	✅SUCCESS	点此跳转
开源合规检查	✅SUCCESS	点此跳转
UT测试	❌FAILED	点此跳转
ST测试	N/A	N/A
build 编译包	N/A	N/A
ruff codecheck	✅SUCCESS	N/A