lint: ruff format + one auto-fix so the push self-test is green again

`scripts/lint.sh --fix` from the pinned lint devshell: 90 Python files
reformatted (ruff format, mechanical) and one C420 (dict comprehension →
dict.fromkeys) in tests/unit/test_f211_sso_skip.py. The push self-test had
been failing at the lint stage since build 1313 (2026-08-31) on exactly
these files; nothing else changed.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FqkQq3CDmFWcQ7u1LzoyRz

tests/gitea/ops.py

@@ -220,7 +220,7 @@ def pre_restore(ctx):
     generic.assert_serving(ctx.domain, ctx.meta)
     ok = _delete_marker_repo(ctx.domain, user, password)
     assert ok, f"pre_restore: could not delete {_MARKER_REPO} repo on {ctx.domain}"
-    assert not marker_repo_exists(
-        ctx.domain, user, password
-    ), f"pre_restore: {_MARKER_REPO} still present after delete — divergence did not take"
+    assert not marker_repo_exists(ctx.domain, user, password), (
+        f"pre_restore: {_MARKER_REPO} still present after delete — divergence did not take"
+    )
     print(f"  gitea ops: {_MARKER_REPO!r} deleted (diverged from backup state)", flush=True)