chore: ruff auto-fix PLR6201 resweep — tuple → set in membership tests (#27355)

Six days after #23937 (608 fixes) the codebase had accumulated 241 new
PLR6201 violations. Same mechanical `x in (...)` → `x in {...}` fix,
same zero-risk profile: set lookup is O(1) vs O(n) for tuple and the
two are semantically equivalent for hashable scalar membership tests.

All 241 instances fixed via `ruff check --select PLR6201 --fix
--unsafe-fixes`, zero remaining. Every changed value is a hashable
scalar (str/int/None/enum/signal); no risk of unhashable runtime
errors. No behavior change.

Test plan:
- 119 files changed, +244/-244 (net zero) — exactly one-line edits
- `ruff check` clean afterward
- Compile checks pass on the largest touched files (cli.py, run_agent.py,
  gateway/run.py, gateway/platforms/discord.py, model_tools.py)
- Subset broad test run on tests/gateway/ tests/hermes_cli/ tests/agent/
  tests/tools/: 18187 passed, 59 pre-existing failures (verified against
  origin/main with the same shape — identical failure count, identical
  category — all xdist test-order flakes unrelated to this change)

Follows the same template as PR #23937 ([tracker: #23972](https://github.com/NousResearch/hermes-agent/issues/23972)).

skills/creative/comfyui/scripts/extract_schema.py

@@ -81,7 +81,7 @@ def trace_to_node(workflow: dict, link: list, *, max_hops: int = 8) -> str | Non
             return None
         cls = node.get("class_type", "")
         # Reroute / Primitive / passthrough wrappers
-        if cls in ("Reroute", "PrimitiveNode", "Note", "easy showAnything"):
+        if cls in {"Reroute", "PrimitiveNode", "Note", "easy showAnything"}:
             inputs = node.get("inputs", {}) or {}
             # Find first link-shaped input and follow it
             next_link = next((v for v in inputs.values() if is_link(v)), None)
@@ -105,7 +105,7 @@ def find_negative_prompt_node(workflow: dict) -> str | None:
         src = trace_to_node(workflow, neg)
         if src and isinstance(workflow.get(src), dict):
             cls = workflow[src].get("class_type", "")
-            if cls.startswith("CLIPTextEncode") or cls in ("smZ CLIPTextEncode", "BNK_CLIPTextEncodeAdvanced"):
+            if cls.startswith("CLIPTextEncode") or cls in {"smZ CLIPTextEncode", "BNK_CLIPTextEncodeAdvanced"}:
                 return src
     return None
 
@@ -121,7 +121,7 @@ def find_positive_prompt_node(workflow: dict) -> str | None:
         src = trace_to_node(workflow, pos)
         if src and isinstance(workflow.get(src), dict):
             cls = workflow[src].get("class_type", "")
-            if cls.startswith("CLIPTextEncode") or cls in ("smZ CLIPTextEncode", "BNK_CLIPTextEncodeAdvanced"):
+            if cls.startswith("CLIPTextEncode") or cls in {"smZ CLIPTextEncode", "BNK_CLIPTextEncodeAdvanced"}:
                 return src
     return None