Task boards show rollout audit lines as titles for event-only Todos

[songoow]

Problem

Personal Workspace task boards show titles such as todo add recorded for todo_584f55f8f3b4 for some open Todos (reproducible with the public examples/status.example.json).

These rows come from build_todo_index (loopx/control_plane/todos/todo_index.py). Todos present in the attention queue use their real text, but a Todo that is only known from the rollout event log (for example because the attention queue carries a bounded Todo list) is indexed from the event itself:

• loopx todo add|update|… records the event with summary="todo <command> recorded for <todo_id>" (loopx/cli_commands/todo_event.py);
• _indexed_rollout_todo_event uses that summary as both text and title, falling back to "<event_kind> recorded for <todo_id>".

The event carries no Todo text, so the index has nothing better to show, and the audit sentence reaches the operator as if it were the task.

Options

Both change a control-plane contract, so this needs a maintainer decision before a PR:

1. Record the Todo text on the event — todo_event.py adds a compact, public-safe details.text (same redaction as other Todo text in the status projection), and the index prefers it over the summary. Additive to the append-only event log; events written before the change keep the audit title.
2. Type the title source in the index — _indexed_rollout_todo_event marks such rows (e.g. title_source: "event_audit"), and the workspace renders them as an event-only Todo (id plus last event) instead of a task title. No event-log change; works for existing events.

They are not exclusive: (1) improves new events, (2) makes existing ones honest.

Acceptance

• A rollout-only open Todo never renders … recorded for todo_… as its task title.
• Todos present in the attention queue are unchanged.

[kokokoXUY]

Opened #5312 for this: the projection now labels event-only Todos by todo_id
(title_source: "event_audit") and keeps the rollout audit sentence in a new
latest_event_summary field, so todo add recorded for todo_… is no longer
rendered as a task title.

I took option 2 rather than option 1 because the rollout event log deliberately
declares boundary.raw_task_text_recorded: False
(loopx/rollout_event_log.py), and writing Todo text into details.text would
turn an accepted loopx todo add --text "..." into a hard failure whenever
FORBIDDEN_TEXT_MARKERS rejects a benign string (for example
Rotate the api_key documentation passes the projection's public-safe
compaction but is rejected by the event log's stricter markers). Option 2 also
corrects existing runtime logs without a migration.

Behavior after the change:

• event-only row -> text/title = todo <todo_id>,
  title_source: "event_audit", audit sentence in latest_event_summary;
• attention-queue row -> unchanged text, no title_source, only
  latest_event_summary follows the newest event.

Validation on the PR head: 11 passed in
tests/control_plane/test_status_rollout_event_snapshot.py (three new behavior
tests), 38 passed with the adjacent todo/lifecycle/lane projection suites, a
revert-the-fix mutation fails the three new tests, and
examples/status.example.json is refreshed to the fixed shape so the public
dashboard example no longer shows audit lines as titles.