fix(session): alert for an agent waiting on artifact comments

An agent that publishes an artifact arms a monitor for its comments and
ends its turn. Claude Code shows that on the footer as `1 Artifact
comment monitor`, and #473 put that chip on the list of background work,
so the session counted as watching and its idle prompt opened already
acknowledged. Unlike every other chip on the list, that monitor waits
on the user: the agent hears nothing until somebody comments.

Claude's `watchingLine` now refuses any footer that carries the chip,
through a lookahead over the whole row, so a shell running beside the
monitor cannot report the session as watching either.

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

docs/cli-registry.md

@@ -66,6 +66,9 @@ agents` while a monitor, a backgrounded shell or a cloud session is live. Codema
 into `Session.watching`, and an idle prompt from such a session opens already acknowledged,
 so a pane waiting for its own background work never raises an alert a human cannot answer.
 Group 1 is the label, and a CLI that declares no pattern reports no background work.
+Claude's Artifact comment monitor is the one chip that does not count. It waits for a human
+to comment on a page the agent published, so Claude's pattern refuses any footer that
+carries it, and the idle alert goes out as usual.
 
 Two CLIs declare such a row today, and they put it in different places. Claude writes its
 chip on the last row of the screen, so it keeps the default one-row window and anchors on

docs/wiki/Notifications-And-Approvals.md

@@ -127,6 +127,10 @@ plain prose is not a dialog, so an agent that starts a monitor and then writes "
 should I target?" is quiet along with the rest — check a watching session yourself if it has
 been quiet longer than the work it is waiting for should take.
 
+An agent waiting for your comments on an artifact it published never counts as watching.
+Claude shows that as "1 Artifact comment monitor", but the agent hears nothing until you
+comment, so the session alerts you like any other quiet session.
+
 ## The phone overview
 
 On phones, tapping the "C" logo gives a session overview with **NEEDS YOU** first, then