fix(terminal): strip VIRTUAL_ENV/CONDA_PREFIX from terminal subprocess env

The Hermes gateway runs inside its own venv, so its process environment
carries VIRTUAL_ENV (and possibly CONDA_PREFIX). The terminal tool spawned
subprocesses inheriting those markers. When the agent ran `uv sync`,
`uv pip install`, `poetry install`, etc. in ANY other project directory,
those tools honored the inherited VIRTUAL_ENV and rebuilt/synced that
project's dependencies into the Hermes venv path — wiping Hermes' own runtime
deps (and, when the other project pinned a different Python, replacing the
interpreter), bricking the gateway on the next restart (#23473).

Strip VIRTUAL_ENV/CONDA_PREFIX in both subprocess-env construction points in
tools/environments/local.py — `_sanitize_subprocess_env` and `_make_run_env`
— via a shared `_ACTIVE_VENV_MARKER_VARS` constant. The Hermes venv stays
reachable because its bin dir is already first on PATH, so removing the
active-environment markers is safe and only prevents the cross-project clobber.

Adds TestActiveVenvMarkerStripping: end-to-end (markers in os.environ don't
reach the spawned subprocess) and unit coverage for both functions, plus a
guard on the marker constant.

Also adds the AUTHOR_MAP entry for the salvaged contributor.

Closes #23473

tests/tools/test_local_env_blocklist.py

@@ -239,6 +239,54 @@ class TestForceEnvOptIn:
         assert result_env["OPENAI_BASE_URL"] == "http://intended/v1"
 
 
+class TestActiveVenvMarkerStripping:
+    """Active-virtualenv markers must not leak into terminal subprocesses (#23473).
+
+    The gateway runs inside its own venv, so its process environment carries
+    VIRTUAL_ENV (and possibly CONDA_PREFIX). If those leak into commands the
+    agent runs against ANOTHER Python project, ``uv``/``poetry`` treat the
+    inherited value as the active environment and build that project's deps
+    into the Hermes venv path instead of the project's own ``.venv`` —
+    silently clobbering the Hermes environment (and, when the other project
+    pins a different Python, breaking the gateway outright). The Hermes venv
+    stays reachable via PATH, so stripping the markers is safe.
+    """
+
+    def test_virtualenv_marker_stripped_end_to_end(self):
+        result_env = _run_with_env(extra_os_env={
+            "VIRTUAL_ENV": "/home/user/.hermes/hermes-agent/venv",
+        })
+        assert "VIRTUAL_ENV" not in result_env
+
+    def test_conda_prefix_marker_stripped_end_to_end(self):
+        result_env = _run_with_env(extra_os_env={
+            "CONDA_PREFIX": "/opt/conda/envs/hermes",
+        })
+        assert "CONDA_PREFIX" not in result_env
+
+    def test_make_run_env_strips_markers(self):
+        from tools.environments.local import _make_run_env
+        poison = {"VIRTUAL_ENV": "/venv", "CONDA_PREFIX": "/conda", "PATH": "/usr/bin"}
+        with patch.dict(os.environ, poison, clear=True):
+            result = _make_run_env({})
+        assert "VIRTUAL_ENV" not in result
+        assert "CONDA_PREFIX" not in result
+
+    def test_sanitize_subprocess_env_strips_markers(self):
+        from tools.environments.local import _sanitize_subprocess_env
+        base = {"VIRTUAL_ENV": "/venv", "CONDA_PREFIX": "/conda", "HOME": "/home/user"}
+        # Even an explicitly-passed extra marker is stripped.
+        result = _sanitize_subprocess_env(base, {"VIRTUAL_ENV": "/also/venv"})
+        assert "VIRTUAL_ENV" not in result
+        assert "CONDA_PREFIX" not in result
+        assert result.get("HOME") == "/home/user"
+
+    def test_markers_constant_contents(self):
+        from tools.environments.local import _ACTIVE_VENV_MARKER_VARS
+        assert "VIRTUAL_ENV" in _ACTIVE_VENV_MARKER_VARS
+        assert "CONDA_PREFIX" in _ACTIVE_VENV_MARKER_VARS
+
+
 class TestBlocklistCoverage:
     """Sanity checks that the blocklist covers all known providers."""