Alternative approach: Remove timeout mechanism, rely on stream cleanup

This commit demonstrates that PR #559's stream cleanup alone is sufficient
to prevent hanging, even with servers that ignore SIGTERM. Testing shows:

1. PR #559 stream cleanup alone handles all tested hanging scenarios
2. Timeout mechanism may be unnecessary additional complexity
3. Existing Unix behavior works fine without timeouts
4. Original timeout tests still pass, confirming no regression

This simpler approach preserves Unix behavior while eliminating
platform-specific timeout handling complexity.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: felixweinberger

src/mcp/client/stdio/__init__.py

@@ -178,13 +178,7 @@ async def stdin_writer():
             yield read_stream, write_stream
         finally:
             # Clean up process to prevent any dangling orphaned processes
-            try:
-                process.terminate()
-                with anyio.fail_after(2.0):
-                    await process.wait()
-            except TimeoutError:
-                # Force kill if it doesn't terminate
-                process.kill()
+            process.terminate()
             await read_stream.aclose()
             await write_stream.aclose()
             await read_stream_writer.aclose()