[tempus2016]

fix(cards): pre-reader tiles lock a recurring chore in its cooldown

With pre_reader: true, a recurring chore waiting to reset stayed a live tile:
the tile checked a flag nothing ever set, so a tap went through. The same
was true of a sibling's first-come claim, a filled weekly target, a missed
time window, a chore not due today (due_days_mode: dim) and a set time that
isn't open.

The tile now takes its locks from the same helper as the classic row,
_choreLocks, so it is greyed out and does nothing when tapped in exactly the
cases the standard row refuses. A chore ticked today keeps its undo. The
dead _isAvailableForChild flag is gone, and the wiki no longer lists
pre-reader tiles as ignoring first_come_claimed_mode / recurrence_done_mode.

docs(wiki): pre-reader tiles honour the first-come claimed lock

The first-come section still listed pre-reader tiles as ignoring the lock
after the tile fix; only timed-task cards are left uncovered there.

Testing

• Unit and frontend tests for this change are included in the diff; the whole batch passes the full suite.
• Checked on the dev Home Assistant instance as part of the v7.7.1 pre-release gate (desktop and 360/375/393/768 phone/tablet widths).