feat: Claude Code Monitor — lanes, pipelines and a merged workspace

Internal SmartGift build of a Claude Code monitoring dashboard.

Lanes: a durable unit of parallel agent work, one per working directory,
tracked across session restarts. Managed lanes are git worktrees the
dashboard provisions and can reset or remove behind a three-check destroy
guard and a counted preflight; adopted lanes are directories you already
own and are never destroyable.

Pipelines: a lane moves through pipeline stages. A stage the agent declares
with evidence renders green; a stage inferred from the tool-event stream
renders dashed amber and never counts as done. Detection is forward-only
within a 30-minute window, and never writes the declared stage.

Workspace: one page at /run with a lane grid, the selected lane's pipeline,
and a full Claude console behind a disclosure.

plugins/ccam-sessions/commands/recent.md

@@ -0,0 +1,27 @@
+---
+description: List the N most recent Claude Code sessions from the Agent Monitor.
+argument-hint: "[N]"
+---
+
+List the most recent Claude Code sessions tracked by the Agent Monitor.
+
+`N` = **$ARGUMENTS** (default `10` if empty).
+
+Fetch the most recent sessions (the API returns them most-recently-updated first):
+
+```
+curl -s "http://localhost:4820/api/sessions?limit=$ARGUMENTS"
+```
+
+This returns a session list; each entry has id, status, model, cwd, started_at,
+ended_at, cost, and metadata (turn_count, total_turn_duration_ms).
+
+Then print the sessions as a numbered list, one line each, in the order returned:
+
+`<rank>. <id short> — <status> — <model> — <cwd basename> — <turn_count> turns — $<cost to 4dp> — <started_at>`
+
+After the list, print the summed cost of the listed sessions and a one-line status
+tally (e.g. `7 completed · 2 active · 1 error`).
+
+Currency as USD to 4 decimal places. Keep it terse, no preamble. If the dashboard is
+unreachable, tell the user to start it with `npm start` from the repo root.