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.

runner/harness/deps.py

@@ -28,7 +28,7 @@ from __future__ import annotations
 import contextlib
 import json
 import os
-from typing import Iterable
+from collections.abc import Iterable
 
 from . import lifecycle, naming
 
@@ -36,9 +36,7 @@ from . import lifecycle, naming
 def declared_deps(recipe: str) -> list[str]:
     """Read `DEPS` from `tests/<recipe>/recipe_meta.py` — a list of recipe names this recipe needs
     deployed alongside it. Returns [] if none."""
-    path = os.path.join(
-        os.path.dirname(__file__), "..", "..", "tests", recipe, "recipe_meta.py"
-    )
+    path = os.path.join(os.path.dirname(__file__), "..", "..", "tests", recipe, "recipe_meta.py")
     if not os.path.exists(path):
         return []
     ns: dict = {}