24-4: Support an emergency one-to-one split/merge in SchemeShard

[snaury]

Changelog entry

...

Changelog category

• Not for changelog (changelog entry is not required)

Description for reviewers

Add a special one-to-one split/merge mode in SchemeShard to use in an emergency, e.g. when we need to garbage collect data that is not accounted by tablets but occupies storage space.

Merges #17642.

[github-actions]

⚪ 2025-04-24 07:49:22 UTC Pre-commit check for f710dab has started.
⚪ 2025-04-24 07:52:30 UTC Build linux-x86_64-release-asan is running...
🔴 2025-04-24 08:09:52 UTC Build failed. see the build logs.
🔴 2025-04-24 08:09:54 UTC Tests run skipped.

[github-actions]

⚪ 2025-04-24 07:49:54 UTC Pre-commit check for f710dab has started.
⚪ 2025-04-24 07:53:18 UTC Build linux-x86_64-relwithdebinfo is running...
🔴 2025-04-24 08:12:34 UTC Build failed. see the build logs.
🔴 2025-04-24 08:12:36 UTC Tests run skipped.

[github-actions]

⚪ 2025-04-24 08:21:09 UTC Pre-commit check for 3a483b9 has started.
⚪ 2025-04-24 08:24:15 UTC Build linux-x86_64-relwithdebinfo is running...
🟢 2025-04-24 09:19:03 UTC Build successful.
⚪ 2025-04-24 09:19:21 UTC Tests are running...
🔴 2025-04-24 11:13:28 UTC Some tests failed, follow the links below.

Test history | Test log

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
40502	35222	0	23	5218	39

🟡 2025-04-24 11:14:38 UTC ydbd size 8.3 GiB changed* by +178.8 KiB, which is >= 100.0 KiB vs stable-24-4: Warning

ydbd size dash	stable-24-4: 81ecefd	merge: 3a483b9	diff	diff %
ydbd size	8 898 250 112 Bytes	8 898 433 192 Bytes	+178.8 KiB	+0.002%
ydbd stripped size	485 018 312 Bytes	485 027 016 Bytes	+8.5 KiB	+0.002%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}

[github-actions]

⚪ 2025-04-24 08:31:14 UTC Pre-commit check for 3a483b9 has started.
⚪ 2025-04-24 08:34:16 UTC Build linux-x86_64-release-asan is running...
🟢 2025-04-24 09:08:42 UTC Build successful.
⚪ 2025-04-24 09:09:00 UTC Tests are running...
🔴 2025-04-24 11:21:02 UTC Some tests failed, follow the links below.

Test history | Test log

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
11809	11703	0	34	31	41

🟡 2025-04-24 11:22:01 UTC ydbd size 5.6 GiB changed* by +183.6 KiB, which is >= 100.0 KiB vs stable-24-4: Warning

ydbd size dash	stable-24-4: 81ecefd	merge: 3a483b9	diff	diff %
ydbd size	6 027 675 320 Bytes	6 027 863 312 Bytes	+183.6 KiB	+0.003%
ydbd stripped size	1 508 452 160 Bytes	1 508 485 728 Bytes	+32.8 KiB	+0.002%

^{*please be aware that the difference is based on comparing your commit and the last completed build from the post-commit, check comparation}