Task manager tasks covering reshard compaction.
Reattempt on https://github.com/scylladb/scylladb/pull/14044. Bugfix for https://github.com/scylladb/scylladb/issues/14618 is squashed with 95191f4.
Regression test added.
Closes#14739
* github.com:scylladb/scylladb:
test: add test for resharding with non-empty owned_ranges_ptr
test: extend test_compaction_task.py to test resharding compaction
compaction: add shard_reshard_sstables_compaction_task_impl
compaction: invoke resharding on sharded database
compaction: move run_resharding_jobs into reshard_sstables_compaction_task_impl::run()
compaction: add reshard_sstables_compaction_task_impl
compaction: create resharding_compaction_task_impl