Tool gateway call log

One row per tool call, newest first: which tool, which key, status, latency, guardrail outcome and error code. Never the arguments or the result — they are not stored. band is errors (failed calls — since 2026-09-27 NOT the calls a rule stopped or whose answer the guardrail withheld), stopped (calls a rule stopped before the tool: approval, a limit, the guardrail on the arguments) or guardrail; endpoint narrows to one tool (mcp:<server>/<tool>). Keyset-paginated: pass the previous response's nextCursor as cursor. Requires usage:read.