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>

src/config/cli-registry/stock.ts

@@ -237,7 +237,15 @@ const CLAUDE: CliEntry = {
       // carry a count. A footer that ever drew the chip as its only item would report no
       // watching rather than open that door. See `watchingLabel()` in
       // `session-activity.ts`.
-      watchingLine: String.raw`·\s*(\d+ (?:monitors?|shells?|teams?|local agents?|cloud sessions?|MCP tasks?|background tasks?|(?:background|remote) dynamic workflows?|Artifact comment monitors?))`,
+      // ⚠️ An Artifact comment monitor is the one chip that waits on the user. The agent
+      // has published a page and hears nothing until somebody comments on it, so the
+      // lookahead refuses the whole row while that chip is on it, whatever else is
+      // running beside it. The `^` is what makes the lookahead judge the row once:
+      // without it the engine retries from each later position, and a start past the
+      // chip reports the shell beside it. The lookahead stops short of "monitor", so a
+      // footer cut off mid-chip still counts. Counting the chip as watching kept the
+      // idle alert quiet for a session that was waiting for a human.
+      watchingLine: String.raw`^(?!.*Artifact comment).*?·\s*(\d+ (?:monitors?|shells?|teams?|local agents?|cloud sessions?|MCP tasks?|background tasks?|(?:background|remote) dynamic workflows?))`,
     },
     requiresMux: false,
     // Claude installs Codeman's own hooks block into every workspace it runs in, so its