fix(perf): hand host binaries the host environment in the baseline script

nvidia-smi (vram_mib) and wtype (inject probe) ran without env=host_env(),
so under an AppImage bundle they inherit the bundle's library paths. The
AST guard now covers the measurement script as well as src/vocalinux, and
the script gains the module logger the Style rules require.

scripts/measure_perf_baseline.py

@@ -12,6 +12,7 @@ from __future__ import annotations
 
 import argparse
 import json
+import logging
 import math
 import os
 import platform
@@ -23,6 +24,8 @@ import time
 from pathlib import Path
 from typing import Any, Optional
 
+logger = logging.getLogger(__name__)
+
 PROTOCOL_VERSION = "1.0.0"
 
 _VMRSS_RE = re.compile(r"^VmRSS:\s+(\d+)\s+kB", re.MULTILINE)
@@ -117,6 +120,9 @@ def parse_nvidia_smi_memory(csv_text: str) -> Optional[tuple[int, int]]:
 
 def vram_mib() -> Optional[tuple[int, int]]:
     """Return ``(total_mib, free_mib)`` of the first NVIDIA GPU, if any."""
+    # Lazy: the parse-only subcommands must run without the package installed.
+    from vocalinux.utils.host_process import host_env
+
     try:
         proc = subprocess.run(
             [
@@ -127,8 +133,10 @@ def vram_mib() -> Optional[tuple[int, int]]:
             capture_output=True,
             text=True,
             timeout=30,
+            env=host_env(),
         )
-    except (OSError, subprocess.SubprocessError):
+    except (OSError, subprocess.SubprocessError) as error:
+        logger.debug("nvidia-smi unavailable: %s", error)
         return None
     if proc.returncode != 0:
         return None
@@ -441,6 +449,8 @@ def cmd_inject_probe(args: argparse.Namespace) -> int:
     if wayland:
         import shutil
 
+        from vocalinux.utils.host_process import host_env
+
         if shutil.which("wtype") is not None and backend != "x11":
             for _ in range(5):
                 begin = time.monotonic()
@@ -449,6 +459,7 @@ def cmd_inject_probe(args: argparse.Namespace) -> int:
                     capture_output=True,
                     text=True,
                     timeout=10,
+                    env=host_env(),
                 )
                 wtype_roundtrips.append(time.monotonic() - begin)
     try:

tests/test_host_process.py

@@ -14,6 +14,10 @@ from vocalinux.utils.host_process import host_env
 
 REPO_ROOT = Path(__file__).resolve().parents[1]
 SOURCE = REPO_ROOT / "src" / "vocalinux"
+#: The measurement script drives the app's own probes (nvidia-smi, wtype, the
+#: injector) on the target machine, so it obeys the same rule as the package.
+#: Build-tool scripts (uv, git, cmake) run outside any bundle and are exempt.
+MEASUREMENT_SCRIPT = REPO_ROOT / "scripts" / "measure_perf_baseline.py"
 SUBPROCESS_FUNCS = {"run", "Popen", "check_output", "check_call", "call"}
 
 
@@ -78,7 +82,7 @@ def test_host_binaries_get_a_stripped_environment_and_our_own_python_does_not():
     dies on the wrong GLib, and our own interpreter stripped of it cannot find
     its stdlib or GI stack."""
     inherit, stripped = [], []
-    for path in sorted(SOURCE.rglob("*.py")):
+    for path in sorted([*SOURCE.rglob("*.py"), MEASUREMENT_SCRIPT]):
         for node in ast.walk(ast.parse(path.read_text(encoding="utf-8"))):
             if not _is_subprocess_call(node):
                 continue