fix(voice_mode): restore audio-env detection across clean/WSL/Termux scenarios

Commit 5e1197a4 swapped the inline `os.path.exists('/.dockerenv')` check in
`detect_audio_environment()` for the more thorough `is_container()` helper
in `hermes_constants` (also matches /run/.containerenv and /proc/1/cgroup
markers, with module-level caching). That helper correctly returns True on
CI runners that themselves run inside Docker, which silently appended a
"Running inside Docker container" warning to every detection scenario and
broke four tests whose contract is "should be available":

  - test_clean_environment_is_available
  - test_wsl_with_pulse_allows_voice
  - test_wsl_device_query_fails_with_pulse_continues
  - test_termux_api_microphone_allows_voice_without_sounddevice

The five "should be blocked" sibling tests passed only by coincidence —
the extra container warning still left `available=False`.

Fix:
  - Hoist `is_container` to a module-level import in tools/voice_mode.py
    so it's reachable as `tools.voice_mode.is_container` (matches the
    monkeypatch convention used elsewhere in the test file for `shutil`,
    `_import_audio`, `_termux_api_app_installed`, etc).
  - Add an autouse fixture in `TestDetectAudioEnvironment` defaulting
    `is_container` to False, so tests don't inherit the host runner's
    container state. Per `feedback_no_such_thing_as_flakes`: the failures
    were a real environmental coupling bug, not a flake.
  - Add `test_docker_container_blocks_voice` to preserve and pin the
    container-blocks-voice intent that the original inline check encoded.

Partial close hermes-agent#9.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tests/tools/test_voice_mode.py

@@ -61,6 +61,16 @@ def mock_sd(monkeypatch):
 # ============================================================================
 
 class TestDetectAudioEnvironment:
+    @pytest.fixture(autouse=True)
+    def _isolate_container_detection(self, monkeypatch):
+        """Default `is_container` to False so tests don't inherit the host
+        runner's container state (e.g. CI itself runs inside Docker, where
+        the production `is_container()` returns True via /.dockerenv or
+        /proc/1/cgroup and silently appended a 'Running inside Docker'
+        warning to every scenario). Individual tests opt in via setattr.
+        """
+        monkeypatch.setattr("tools.voice_mode.is_container", lambda: False)
+
     def test_clean_environment_is_available(self, monkeypatch):
         """No SSH, Docker, or WSL — should be available."""
         monkeypatch.delenv("SSH_CLIENT", raising=False)
@@ -85,6 +95,20 @@ class TestDetectAudioEnvironment:
         assert result["available"] is False
         assert any("SSH" in w for w in result["warnings"])
 
+    def test_docker_container_blocks_voice(self, monkeypatch):
+        """Running inside a Docker/Podman container should block voice mode."""
+        monkeypatch.delenv("SSH_CLIENT", raising=False)
+        monkeypatch.delenv("SSH_TTY", raising=False)
+        monkeypatch.delenv("SSH_CONNECTION", raising=False)
+        monkeypatch.setattr("tools.voice_mode.is_container", lambda: True)
+        monkeypatch.setattr("tools.voice_mode._import_audio",
+                            lambda: (MagicMock(), MagicMock()))
+
+        from tools.voice_mode import detect_audio_environment
+        result = detect_audio_environment()
+        assert result["available"] is False
+        assert any("Docker container" in w for w in result["warnings"])
+
     def test_wsl_without_pulse_blocks_voice(self, monkeypatch, tmp_path):
         """WSL without PULSE_SERVER should block voice mode."""
         monkeypatch.delenv("SSH_CLIENT", raising=False)

tools/voice_mode.py

@@ -49,7 +49,7 @@ def _audio_available() -> bool:
         return False
 
 
-from hermes_constants import is_termux as _is_termux_environment
+from hermes_constants import is_container, is_termux as _is_termux_environment
 
 
 def _voice_capture_install_hint() -> str:
@@ -103,7 +103,6 @@ def detect_audio_environment() -> dict:
         warnings.append("Running over SSH -- no audio devices available")
 
     # Docker/Podman container detection
-    from hermes_constants import is_container
     if is_container():
         warnings.append("Running inside Docker container -- no audio devices")