chore: ruff auto-fix PLR6201 — tuple → set in membership tests (#23937)

Replace  with  for all literal-tuple
membership tests. Set lookup is O(1) vs O(n) for tuple — consistent
micro-optimization across the codebase.

608 instances fixed via `ruff --fix --unsafe-fixes`, 0 remaining.
133 files, +626/-626 (net zero).

tools/osv_check.py

@@ -65,9 +65,9 @@ def check_package_for_malware(
 def _infer_ecosystem(command: str) -> Optional[str]:
     """Infer package ecosystem from the command name."""
     base = os.path.basename(command).lower()
-    if base in ("npx", "npx.cmd"):
+    if base in {"npx", "npx.cmd"}:
         return "npm"
-    if base in ("uvx", "uvx.cmd", "pipx"):
+    if base in {"uvx", "uvx.cmd", "pipx"}:
         return "PyPI"
     return None