Preparing to add fs export

[stanislav-shchetinin]

Changelog entry

...

Changelog category

• Not for changelog (changelog entry is not required)

Description for reviewers

...

[github-actions]

🟢 2025-12-18 17:05:13 UTC The validation of the Pull Request description is successful.

[Copilot]

Copilot encountered an error and was unable to review this pull request. You can try again by re-requesting a review.

[github-actions]

⚪ 2025-12-19 14:07:33 UTC Pre-commit check linux-x86_64-release-asan for 2ad2563 has started.
⚪ 2025-12-19 14:11:02 UTC Artifacts will be uploaded here
⚪ 2025-12-19 14:12:57 UTC ya make is running...
🟡 2025-12-19 15:24:18 UTC Some tests failed, follow the links below. This fail is not in blocking policy yet

Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
14349	14183	0	139	7	20

🟢 2025-12-19 15:24:34 UTC Build successful.
🟢 2025-12-19 15:25:08 UTC ydbd size 3.8 GiB changed* by +72.1 KiB, which is < 100.0 KiB vs main: OK

ydbd size dash	main: abc16f1	merge: 2ad2563	diff	diff %
ydbd size	4 083 933 408 Bytes	4 084 007 272 Bytes	+72.1 KiB	+0.002%
ydbd stripped size	1 529 361 080 Bytes	1 529 376 152 Bytes	+14.7 KiB	+0.001%

^{*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]

⚪ 2025-12-19 14:18:28 UTC Pre-commit check linux-x86_64-relwithdebinfo for 2ad2563 has started.
⚪ 2025-12-19 14:19:07 UTC Artifacts will be uploaded here
⚪ 2025-12-19 14:21:20 UTC ya make is running...
🟡 2025-12-19 16:18:30 UTC Some tests failed, follow the links below. Going to retry failed tests...

Details

Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
44012	40951	0	6	3017	38

⚪ 2025-12-19 16:18:50 UTC ya make is running... (failed tests rerun, try 2)
🟢 2025-12-19 16:29:22 UTC Tests successful.

Ya make output | Test bloat | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
388 (only retried tests)	371	0	0	0	17

🟢 2025-12-19 16:29:29 UTC Build successful.
🟢 2025-12-19 16:29:54 UTC ydbd size 2.3 GiB changed* by +7.3 KiB, which is < 100.0 KiB vs main: OK

ydbd size dash	main: b94c296	merge: 2ad2563	diff	diff %
ydbd size	2 484 774 600 Bytes	2 484 782 040 Bytes	+7.3 KiB	+0.000%
ydbd stripped size	528 964 736 Bytes	528 968 640 Bytes	+3.8 KiB	+0.001%

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