Show task, active project and workspace per control board row (#1503)

Gate A fix asked by the professor session on Jason's behalf. Each row
now carries three derived fields, shown as "unknown" when the log and
tmux do not hold them:

- task: the session's first user message (pi logs have no task envelope)
- workspace: the live pane path of the pane running pi, else session cwd
- activeProject: basename of the nearest git checkout above the workspace

tmuxInspect replaces the bare liveness call in the CLI and returns
{ alive, workspace }; tmuxIsAlive stays as a wrapper. The grouping column
and seen.json keys are unchanged. Fixture test per field, tmux parse
tests, page test; missing launcher signals are recorded in the plan page.

Co-Authored-By: Claude Fable 5.1 <[email protected]>

packages/control-board/README.md

@@ -95,6 +95,23 @@ only when Jason clicks "Seen" or "Unsee" on the page (via `POST
 the agent's newest message still has that exact `lastActivity` timestamp —
 as soon as the agent writes anything new, `lastActivity` changes, the mark
 no longer matches, and the row falls back into "Waiting on you" on its own.
+Every row also shows three "what and where" fields, each derived from the
+session log and tmux or shown as the word "unknown", never guessed:
+
+- **Task** — the session's first user message (collapsed to one line, 240
+  characters). pi logs carry no task envelope, so this is the only
+  assignment signal available. For fleet seats it is usually the
+  fleet-comms envelope the seat was started with.
+- **Active project** — the basename of the nearest git checkout (a `.git`
+  directory or worktree file) above the workspace. Fleet seats that run in
+  `~/.mosaic` therefore show `.mosaic`. The grouping column "Project" is
+  unchanged: it still comes from where the seat's logs live, and `seen.json`
+  keys depend on it.
+- **Workspace** (detail row, and the hover title of Active project) — the
+  current path of the tmux pane running `pi`; when the seat is offline or
+  tmux could not be asked, the `cwd` from the session log. The record says
+  which one it used (`workspaceSource`: `tmux-pane` or `session-cwd`).
+
 Marked rows are listed under a collapsed "Seen (N)" section on the page,
 each with an "Unsee" button, so nothing marked is ever out of reach. Each
 project table has "Hide offline" and "Hide seen" checkboxes (both on by
@@ -118,6 +135,11 @@ values), the scan refuses rather than silently dropping every mark.
   "sessionFile": "/mnt/storage/src/mosaic-stack/.pi/state/darkwing/sessions/2026-09-12.jsonl",
   "sessionId": "01a06e48-0718-71f2-a889-c263c4800fb9",
   "cwd": "/mnt/storage/src/mosaic-stack",
+  "task": "Read agents/darkwing/work/RESTART.md",
+  "taskSource": "first-user-message",
+  "workspace": "/mnt/storage/src/mosaic-stack",
+  "workspaceSource": "tmux-pane",
+  "activeProject": "mosaic-stack",
   "lastActivity": "2026-09-12T15:04:33.000Z",
   "ageSeconds": 42,
   "lastAssistantText": "Ready for the next step whenever you are.",