feat(workflows): add task-review list-hygiene habit

The new task-review.org workflow is the daily habit that retires the old date-coverage scan. It surfaces the oldest-unreviewed top-level tasks, walks them one at a time, and records each outcome — keep, re-grade, kill, mark DOING, or edit — stamping :LAST_REVIEWED: as it goes. It's a pure Claude workflow, no elisp. open-tasks.org displays the list; this one changes it.

task-review-staleness.sh gains a --list mode that emits the N oldest-unreviewed tasks (line, review date, heading), oldest first, so the workflow walks a deterministic batch instead of eyeballing todo.org. Never-reviewed and unparseable-date tasks sort oldest. Seven new bats cases cover ordering, the count limit, exclusions, and output format; count mode is unchanged.

startup.org gains the matching nudge. Phase A counts tasks unreviewed for >7 days and Phase C surfaces one line when that count is non-zero, pointing at the workflow. It lives in the template startup.org rather than the project-only startup-extras layer, so every project picks it up the same way it picks up the wrap-up health check.

The INDEX entry is added with the "task review" triggers the rename freed up.

1 files changed, 2 insertions, 0 deletions

diff --git a/.ai/workflows/startup.org b/.ai/workflows/startup.org
index fabd607..3503a60 100644
--- a/.ai/workflows/startup.org
+++ b/.ai/workflows/startup.org
@@ -103,6 +103,7 @@ These calls have no dependencies on each other. Issue them all together in one m
 8. =cross-agent-status 2>/dev/null || true= — snapshot of pending cross-agent messages across local projects. This is layer A of the cold-start design from =cross-agent-comms.org=: pending messages from other agents (delivered while no session was active here) get surfaced on session start. The =|| true= keeps Phase A from failing if =cross-agent-status= isn't installed yet — older projects without the script still boot cleanly. If HALT is active, =cross-agent-status= prints a banner; surface that prominently in Phase C.
 9. Read =.ai/notes.org= — Project-Specific Context, Active Reminders, Pending Decisions sections (skip About This File).
 10. Read =.ai/project-workflows/startup-extras.org= if it exists.
+11. =[ -f todo.org ] && .ai/scripts/task-review-staleness.sh todo.org 7 || true= — count top-level tasks overdue for review (the daily task-review habit's startup nudge). The =[ -f todo.org ]= guard skips projects without a root todo.org; =|| true= keeps Phase A from failing if the script isn't synced yet. Threshold 7 days is one review cycle of slack — softer than the wrap-up health check's 30-day alarm.
 
 Notes on the rsync commands:
 - Trailing slashes on both source and destination matter — they tell rsync to sync /contents/ rather than nest a directory inside.
@@ -131,6 +132,7 @@ This phase touches the user and runs sequentially:
    - Surface Active Reminders from notes.org immediately.
    - Mention Pending Decisions from notes.org.
    - Briefly note significant template updates noticed during sync (new workflows, protocol changes).
+   - *Task-review nudge.* If the Phase A staleness count (step 11) is greater than zero, surface one line: "=<N>= top-level tasks unreviewed for >7 days — say 'let's do a task review' to run a cycle." If zero, say nothing.
    - *Surface pending cross-agent messages.* If =cross-agent-status= reported any pending messages, list them with their =cross-agent-recv= decision (process / query / reject) per file. For =process= messages in this project's inbox, propose handling now or after the current task. For pending in other projects, mention the count so the user knows to switch projects when ready. If HALT was active, surface that prominently — cross-agent activity is paused until =cross-agent-resume= clears it.
 2. *Process inbox if non-empty.* Mandatory — don't ask, just do it. For each file: determine action, recommend filing, get approval, move. For =.eml= files use the extract script (not raw Read):
    #+begin_src bash