fix(traefik): a router's 5xx share is judged only over enough requests, like its 4xx share (#5859)

Two 500s of about sixteen requests graded roundtable@swarm critical at
9.1%. The Settings → Thresholds minimum of requests in 15 minutes (30 by
default) now guards both shares; the 5xx share still keeps its fixed
cutoff whatever the router's history.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

plugins/traefik/mcp_tools.py

@@ -4,7 +4,7 @@ Registered through register_mcp_tools() in __init__.py, so they exist only
 while the plugin is enabled. Routers are graded exactly as the Traefik page
 grades them (routes.py): over the last 15 minutes, the 5xx share against its
 fixed cutoff, the 4xx share and p95 against the router's own normal where it
-has one.
+has one; neither share over fewer requests than Settings → Thresholds asks.
 """
 from __future__ import annotations