style: repo-wide lint pass — make the lint gate green again

Push builds have been RED on the lint step since ~build 209 from accumulated
formatting drift. This is the mechanical cleanup: ruff format + ruff --fix
(UP038 isinstance unions, SIM105 contextlib.suppress, UP031 f-strings, SIM115
tempfile context manager), shfmt -i 2 -ci, nixpkgs-fmt/statix/deadnix (merged
attrsets, dropped unused lib args), yamllint, and shell quoting fixes in
tests/lasuite-docs/setup_custom_tests.sh. No behaviour changes intended;
lint: PASS, unit tests: 138 passed.

tests/unit/test_deps.py

@@ -10,7 +10,6 @@ from __future__ import annotations
 
 import os
 import sys
-import tempfile
 
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "..", "runner"))
 from harness import deps  # noqa: E402
@@ -30,9 +29,7 @@ def test_declared_deps_reads_DEPS_list(tmp_path, monkeypatch):
     # Build a fake repo layout under tmp_path
     recipe_dir = tmp_path / "tests" / fake_recipe
     recipe_dir.mkdir(parents=True)
-    (recipe_dir / "recipe_meta.py").write_text(
-        'HEALTH_PATH = "/"\nDEPS = ["keycloak", "redis"]\n'
-    )
+    (recipe_dir / "recipe_meta.py").write_text('HEALTH_PATH = "/"\nDEPS = ["keycloak", "redis"]\n')
     # Patch the deps module's idea of "where the repo is" by monkey-patching __file__ for the
     # function indirectly: declared_deps uses `os.path.dirname(__file__), "..", "..", "tests"` —
     # which resolves to the real repo's `tests/`. So instead, override that with a symlink/dir