fix(terminal): set MSYS_NO_PATHCONV for Windows Git Bash subprocesses

Git Bash mangles native Windows command flags (/FO, /TN, /Create) into
bogus paths. Hermes terminal and background spawns now opt out by default
so tasklist, schtasks, and wmic work without manual prefixes.

Fixes #56700.

tools/environments/local.py

@@ -383,6 +383,8 @@ def _sanitize_subprocess_env(base_env: dict | None, extra_env: dict | None = Non
     for _marker in _ACTIVE_VENV_MARKER_VARS:
         sanitized.pop(_marker, None)
 
+    _apply_windows_msys_bash_env_defaults(sanitized)
+
     return sanitized
 
 
@@ -493,6 +495,8 @@ def hermes_subprocess_env(*, inherit_credentials: bool = False) -> dict[str, str
     for _marker in _ACTIVE_VENV_MARKER_VARS:
         env.pop(_marker, None)
 
+    _apply_windows_msys_bash_env_defaults(env)
+
     # Cross-session leak guard, same as the terminal spawn paths: this helper
     # copies os.environ, whose HERMES_SESSION_* mirror is a last-writer-wins
     # global under a concurrent multi-session host. A caller that re-binds the
@@ -746,6 +750,21 @@ def _append_missing_sane_path_entries(existing_path: str) -> str:
     return ":".join(ordered_entries)
 
 
+def _apply_windows_msys_bash_env_defaults(env: dict) -> None:
+    """Disable MSYS argument path conversion for Git Bash subprocesses.
+
+    Git Bash rewrites arguments that look like Unix paths (``/FO``, ``/TN``,
+    ``/Create``) into ``C:/.../git/FO``-style paths, which breaks native
+    Windows commands such as ``tasklist``, ``schtasks``, and ``wmic``.  Hermes
+    runs terminal commands through bash on Windows, so set the standard MSYS
+    opt-out by default.  Users who need conversion can override in their env.
+    Refs #56700.
+    """
+    if not _IS_WINDOWS:
+        return
+    env.setdefault("MSYS_NO_PATHCONV", "1")
+
+
 def _path_env_key(run_env: dict) -> str | None:
     """Return the PATH env key to update without altering Windows casing.
 
@@ -804,6 +823,8 @@ def _make_run_env(env: dict) -> dict:
     for _marker in _ACTIVE_VENV_MARKER_VARS:
         run_env.pop(_marker, None)
 
+    _apply_windows_msys_bash_env_defaults(run_env)
+
     return run_env