feat(todo-cleanup): add --convert-subtasks dated-rewrite mode

Rewrites every level-3+ DONE/CANCELLED/FAILED heading into a dated event-log entry from its CLOSED cookie, enforcing the todo-format depth rule that interactive closes and --archive-done (level-2 only) leave unapplied. A new lint-org checker (subtask-done-not-dated) flags stragglers, and the clean-todo, wrap-up, open-tasks, and task-review workflows now run the converter before archiving.

Removing the CLOSED cookie keeps a DEADLINE or SCHEDULED cookie that shares its planning line, rather than dropping the whole line.

From the .emacs.d handoff (2026-07-01 convert-subtasks bundle).

1 files changed, 17 insertions, 1 deletions

diff --git a/.ai/workflows/wrap-it-up.org b/.ai/workflows/wrap-it-up.org
index 5d2cdd2..4fa5a3a 100644
--- a/.ai/workflows/wrap-it-up.org
+++ b/.ai/workflows/wrap-it-up.org
@@ -137,6 +137,22 @@ Run the report-only variant first if you want to see what would change without w
 emacs --batch -q -l .ai/scripts/todo-cleanup.el --check todo.org
 #+end_src
 
+*** Convert done sub-tasks to dated entries
+
+#+begin_src bash
+[ -f todo.org ] && emacs --batch -q -l .ai/scripts/todo-cleanup.el --convert-subtasks todo.org
+#+end_src
+
+=--convert-subtasks= rewrites every heading at level 3 or deeper whose TODO state is DONE/CANCELLED/FAILED into a dated event-log entry (=<stars> YYYY-MM-DD Day @ HH:MM:SS -ZZZZ <text>=), dropping the keyword, priority cookie, and tags, and removing the now-redundant =CLOSED:= line. This enforces the =todo-format.md= depth rule that a completed *sub-task* (a heading under a parent task) becomes dated history, not a lingering DONE keyword — a shape an interactive org close (=org-log-done= → DONE + CLOSED) never applies and =--archive-done= (level-2 only) never reaches. The timestamp comes from each entry's own =CLOSED= cookie; a date-only close yields =00:00:00=. Heading text is kept verbatim. Idempotent (an already-dated heading has no keyword to match), and a done sub-task with no parseable =CLOSED= is flagged and left alone rather than stamped with a fabricated date.
+
+Run this *before* =--archive-done= so that when a completed level-2 parent is archived, its sub-tasks already carry their dated form. Any rewrites show up in the wrap-up commit's diff for review before push.
+
+Preview without writing:
+
+#+begin_src bash
+emacs --batch -q -l .ai/scripts/todo-cleanup.el --convert-subtasks --check todo.org
+#+end_src
+
 *** Archive completed work
 
 #+begin_src bash
@@ -536,7 +552,7 @@ Before considering wrap-up complete:
 - [ ] The Summary ends with the =KB: promoted N / consulted yes-no= line (promotion check ran)
 - [ ] File renamed to =.ai/sessions/YYYY-MM-DD-HH-MM-description.org=
 - [ ] =.ai/session-context.org= no longer exists
-- [ ] =todo-cleanup.el= ran — hygiene pass + =--archive-done= + =--sync-child-priority= (if =todo.org= exists at project root)
+- [ ] =todo-cleanup.el= ran — hygiene pass + =--convert-subtasks= + =--archive-done= + =--sync-child-priority= (if =todo.org= exists at project root)
 - [ ] =lint-org.el= ran on =todo.org= — mechanical fixes applied, judgments appended to follow-ups file (if =todo.org= exists)
 - [ ] Any orphan-planning-line warnings reviewed (fix or accept)
 - [ ] Inbox carries nothing but expected pipeline artifacts (=.gitkeep=, =lint-followups.org=, =PROCESSED-*= prefixes), OR each remaining handoff has an explicit deferral logged in the valediction