fix(git): keep stdio validation errors recoverable

[he-yufeng]

Description

Fixes #4213 by letting the git server use the default Server.run(...) behavior, matching the time server. Validation errors from stdin parsing should be returned through the JSON-RPC error path instead of being re-raised into the server task group and terminating the process.

Server Details

• Server: git
• Changes to: stdio transport error handling

Motivation and Context

mcp-server-git was the outlier among the Python reference servers: it passed raise_exceptions=True into Server.run(...). For malformed JSON-RPC input, that makes transport-level validation errors abort the server process instead of keeping the stdio session recoverable.

The change removes that override and adds a focused regression test that verifies the git server no longer opts into exception-raising transport behavior.

How Has This Been Tested?

• python -m py_compile src\git\src\mcp_server_git\server.py src\git\tests\test_server.py
• python -m pytest src\git\tests\test_server.py::test_stdio_transport_errors_do_not_abort_server -q
• python -m ruff check src\git\src\mcp_server_git\server.py src\git\tests\test_server.py
• git diff --check

I also ran the full python -m pytest src\git\tests\test_server.py -q on Windows. All test assertions reached pass state, but the existing GitPython temp repository fixture hit Windows file-handle cleanup errors during teardown (PermissionError while removing .git temp dirs). I did not count that as a clean full-suite pass.

Breaking Changes

None. This aligns git server transport error behavior with the other Python servers instead of changing tool semantics.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Protocol Documentation
• My changes follows MCP security best practices
• I have updated the server's README accordingly
• I have tested this with an LLM client
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have documented all environment variables and configuration options

Additional context

No README/config changes are needed because this is an internal transport recovery behavior fix.