Fixed processing kafka batch v0 and v1 with many messages

[nshestakov]

Changelog entry

Поправлена ошибка, когда при записи сообщений kafka , использующих формат батча v0 и v1 сохранялось только первое сообщение батча (все остальные игнорировались)

Changelog category

• Bugfix

Description for reviewers

LOGBROKER-9936

[github-actions]

🟢 2025-09-05 11:23:00 UTC The validation of the Pull Request description is successful.

[github-actions]

⚪ 2025-09-05 10:49:15 UTC Pre-commit check linux-x86_64-relwithdebinfo for 90f8925 has started.
⚪ 2025-09-05 10:49:29 UTC Artifacts will be uploaded here
⚪ 2025-09-05 10:52:51 UTC ya make is running...
⚫ 2025-09-05 11:05:22 UTC Check cancelled

[github-actions]

⚪ 2025-09-05 10:49:27 UTC Pre-commit check linux-x86_64-release-asan for 90f8925 has started.
⚪ 2025-09-05 10:49:40 UTC Artifacts will be uploaded here
⚪ 2025-09-05 10:52:58 UTC ya make is running...
⚫ 2025-09-05 11:05:23 UTC Check cancelled

[github-actions]

⚪ 2025-09-05 11:14:42 UTC Pre-commit check linux-x86_64-release-asan for ef450f7 has started.
⚪ 2025-09-05 11:14:57 UTC Artifacts will be uploaded here
⚪ 2025-09-05 11:18:13 UTC ya make is running...
🟡 2025-09-05 13:12:04 UTC Some tests failed, follow the links below. This fail is not in blocking policy yet

Test history | Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
16956	16548	0	105	275	28

🟢 2025-09-05 13:13:31 UTC Build successful.
🟢 2025-09-05 13:13:53 UTC ydbd size 4.0 GiB changed* by +8.0 KiB, which is < 100.0 KiB vs main: OK

ydbd size dash	main: 691cda0	merge: ef450f7	diff	diff %
ydbd size	4 291 117 776 Bytes	4 291 126 008 Bytes	+8.0 KiB	+0.000%
ydbd stripped size	1 487 627 032 Bytes	1 487 630 040 Bytes	+2.9 KiB	+0.000%

^{*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]

⚪ 2025-09-05 11:15:06 UTC Pre-commit check linux-x86_64-relwithdebinfo for ef450f7 has started.
⚪ 2025-09-05 11:15:20 UTC Artifacts will be uploaded here
⚪ 2025-09-05 11:18:37 UTC ya make is running...
🟡 2025-09-05 12:31:23 UTC Some tests failed, follow the links below. Going to retry failed tests...

Test history | Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
32607	31190	0	4	1377	36

⚪ 2025-09-05 12:34:18 UTC ya make is running... (failed tests rerun, try 2)
🟢 2025-09-05 12:47:47 UTC Tests successful.

Test history | Ya make output | Test bloat | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
465 (only retried tests)	434	0	0	4	27

🟢 2025-09-05 12:47:58 UTC Build successful.
🟢 2025-09-05 12:48:14 UTC ydbd size 2.3 GiB changed* by +4.1 KiB, which is < 100.0 KiB vs main: OK

ydbd size dash	main: 691cda0	merge: ef450f7	diff	diff %
ydbd size	2 441 654 408 Bytes	2 441 658 632 Bytes	+4.1 KiB	+0.000%
ydbd stripped size	511 187 176 Bytes	511 188 008 Bytes	+832 Bytes	+0.000%

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