Currently, for repair tasks tablet_virtual_task::wait gathers the
ids of tablets that are to be repaired. The gathered set is later
used to check if the repair is still ongoing.
However, if the tablets are resized (split or merged), the gathered
set becomes irrelevant. Those, we may end up with invalid tablet id
error being thrown.
Wait until repair is done for all tablets in the table.
Fixes: https://github.com/scylladb/scylladb/issues/28202
Backport to 2026.1 needed as it contains the change introducing the issue d51b1fea94Closesscylladb/scylladb#28323
* github.com:scylladb/scylladb:
service: fix indentation
test: add test_tablet_repair_wait
service: remove status_helper::tablets
service: tasks: scan all tablets in tablet_virtual_task::wait
3fed6f9eff