fix(hooks): keep a keep-alive turn's hooks out of the run summary

Merge-time fix for #666. `recordHookEvent()` ran for every `stop`, the run
summary files a `stop` as a warning, and the Away digest lists warnings under
Needs Attention, so each keep-alive nudge added a row there and to the
session's Summary timeline. The hook route now skips the run summary while
`keepAliveReason` is set (the keep-alive turn's `stop` and `idle_prompt`).

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

docs/wiki/Keeping-Agents-Running.md

@@ -115,7 +115,7 @@ It only fires when there is nothing else going on: the session is idle with an e
 
 Recent Claude Code builds can compact a large idle session on their own shortly before the cache expires, which would leave only a summary to keep warm. So a session **started** with keep-warm on also launches with Claude Code's idle compaction switched off (Claude Code 2.1.290 or newer); Codeman then owns the idle policy for it. A session you switch on after it started is still kept warm, but Claude Code may compact it first until its next launch, and the Status line says so; one you switch off keeps Claude Code's idle compaction off until its next launch, and the Status line says that too. Sessions with keep-warm off launch exactly as before.
 
-**Keep prompt caches warm** in the same Automation group is the default for sessions that have not chosen on their Respawn tab; the per-session switch always wins. A session another agent started (a worker) does not follow the default: most workers are never prompted again once they report done, so turn it on for one by hand if you will come back to it. The keep-alive turn is Codeman's, not yours: it does not restart the **Keep warm for at most** window, does not rename a tab, Read My Mind ignores it, and the response it ends with raises no alert, toast, push or webhook. It never clears an alert that was already waiting for you. It is refused on the five-minute cache lifetime, which is what an API key, a cloud provider or extra-usage credits get; a session on an API key can ask Claude Code for the hour with `CLAUDE_CODE_PROMPT_CACHE_TTL=1h` in its environment overrides.
+**Keep prompt caches warm** in the same Automation group is the default for sessions that have not chosen on their Respawn tab; the per-session switch always wins. A session another agent started (a worker) does not follow the default: most workers are never prompted again once they report done, so turn it on for one by hand if you will come back to it. The keep-alive turn is Codeman's, not yours: it does not restart the **Keep warm for at most** window, does not rename a tab, Read My Mind ignores it, and the response it ends with raises no alert, toast, push or webhook, nor a row in the Away digest or the session's Summary. It never clears an alert that was already waiting for you. It is refused on the five-minute cache lifetime, which is what an API key, a cloud provider or extra-usage credits get; a session on an API key can ask Claude Code for the hour with `CLAUDE_CODE_PROMPT_CACHE_TTL=1h` in its environment overrides.
 
 ## The plan usage chip