DebugMCP incorrectly infers .exe target on WSL instead of using existing launch.json program

まず、"Debug nanopb simple" という名前の既存の launch.json 構成がどのように選択され、そこにある fileFullPath と workingDirectory がどのようにデバッグターゲットへ変換されるかを調べます。提供されている cppdbg 構成を使って WSL のケースを再現し、構成されたプログラムパスが使用され、simple.exe ターゲットが生成されないことを確認します。

Environment

• VS Code: 1.119.0
• Platform: Linux (WSL / Dev Container)
• Architecture: x64
• DebugMCP server running successfully
• C/C++ extension installed (ms-vscode.cpptools)
• Debug adapter: cppdbg
• Debugger: gdb

Problem

DebugMCP fails to start an existing C/C++ debug configuration on WSL/Linux.

Manual debugging with F5 works correctly using the existing launch.json.

However, when DebugMCP attempts to start the debug session, it appears to ignore or override the configured "program" field and instead derives a Windows-style executable name from the source file.

It attempts to launch:

/workspaces/ubuntu-c3c/nanopb/build-tests/legacy_cmake_simple/simple.exe

which does not exist.

The real executable is:

/workspaces/ubuntu-c3c/nanopb/build-tests/legacy_cmake_simple/build/simple

Existing launch.json

{
  "name": "Debug nanopb simple",
  "type": "cppdbg",
  "request": "launch",
  "program": "/workspaces/ubuntu-c3c/nanopb/build-tests/legacy_cmake_simple/build/simple",
  "cwd": "/workspaces/ubuntu-c3c/nanopb/build-tests/legacy_cmake_simple/build",
  "MIMode": "gdb",
  "miDebuggerPath": "/usr/bin/gdb"
}

Observed behavior

DebugMCP agent output references:

{
  "fileFullPath": "/workspaces/ubuntu-c3c/nanopb/build-tests/legacy_cmake_simple/simple.c",
  "workingDirectory": "/workspaces/ubuntu-c3c/nanopb/build-tests/legacy_cmake_simple",
  "configurationName": "Debug nanopb simple"
}

and then attempts to launch:

simple.exe

instead of using the configured "program" value from launch.json.

Expected behavior

DebugMCP should:

1. Use the existing VS Code debug configuration exactly as defined
2. Respect the "program" field from launch.json
3. Avoid generating .exe targets on Linux/WSL environments
4. Avoid inferring executables from source filenames when a valid launch configuration already exists

Additional notes

• Starting the debug session manually with F5 works perfectly
• Breakpoints work correctly