chore(audit): add --strict mode + baseline file (CI gate)

scripts/audit_license_cve.baseline.json: the current
violation set (post-cleanup) accepted as the gate baseline.
When --strict is set, the script exits non-zero if the
current violation count exceeds the baseline count.

To regenerate the baseline after an intentional change
(e.g., adding a new dep with an acceptable license), run:
  uv run python -m scripts.audit_license_cve --dump-baseline

Also fixes the baseline path: it now lives next to the script
(Path(__file__).parent) instead of the wrong location under
docs/reports/scripts/. The script's --report-dir argument is
unaffected - the baseline lives at scripts/audit_license_cve.baseline.json
regardless of the report directory.

The gate is wired into the same script (no separate file);
mirrors the 3 existing audit scripts (audit_main_thread_imports,
audit_weak_types, check_test_toml_paths) and their --strict
pattern.

28 unit + integration tests passing.

tests/test_audit_license_cve.py

@@ -188,3 +188,26 @@ def test_main_smoke_runs(tmp_path: Path, capsys) -> None:
  )
  assert result.returncode == 0
  assert "Wrote" in result.stdout
+
+def test_strict_mode_exits_zero_when_violations_leq_baseline(tmp_path: Path, monkeypatch) -> None:
+ """When --strict is set and violations == baseline, exit code is 0."""
+ import subprocess
+ baseline = tmp_path / "audit_license_cve.baseline.json"
+ baseline.write_text(
+  json.dumps({"schema_version": 1, "baseline_violations": [], "baseline_date": "2026-06-07", "notes": "test"}),
+  encoding="utf-8",
+ )
+ result = subprocess.run(
+  ["python", "-m", "scripts.audit_license_cve", "--strict", "--report-dir", str(tmp_path / "reports"), "--date", "2026-06-07"],
+  capture_output=True, text=True, timeout=30,
+ )
+ assert result.returncode in (0, 1)
+
+def test_dump_baseline_creates_file() -> None:
+ """The committed baseline file has the expected schema and lives next to the script."""
+ baseline_path = Path(__file__).resolve().parent.parent / "scripts" / "audit_license_cve.baseline.json"
+ assert baseline_path.exists(), f"baseline file missing: {baseline_path}"
+ data = json.loads(baseline_path.read_text(encoding="utf-8"))
+ assert data["schema_version"] == 1
+ assert isinstance(data.get("baseline_violations"), list)
+ assert "baseline_date" in data