add S3 client knobs + split in‑flight limits (#29541)

[xyliganSereja]

Changelog entry

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Changelog category

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Description for reviewers

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[github-actions]

🟢 2025-12-02 12:30:20 UTC The validation of the Pull Request description is successful.

[github-actions]

⚪ 2025-12-02 12:32:59 UTC Pre-commit check linux-x86_64-relwithdebinfo for 4ba2977 has started.
⚪ 2025-12-02 12:33:14 UTC Artifacts will be uploaded here
⚪ 2025-12-02 12:37:14 UTC ya make is running...
⚫ 2025-12-02 12:39:05 UTC Check cancelled

[github-actions]

⚪ 2025-12-02 12:33:37 UTC Pre-commit check linux-x86_64-release-asan for 4ba2977 has started.
⚪ 2025-12-02 12:33:40 UTC Artifacts will be uploaded here
⚪ 2025-12-02 12:37:46 UTC ya make is running...
⚫ 2025-12-02 12:39:05 UTC Check cancelled

[github-actions]

⚪ 2025-12-02 12:39:53 UTC Pre-commit check linux-x86_64-relwithdebinfo for 83b675d has started.
⚪ 2025-12-02 12:39:57 UTC Artifacts will be uploaded here
⚪ 2025-12-02 12:44:01 UTC ya make is running...
🟡 2025-12-02 14:57:05 UTC Some tests failed, follow the links below. Going to retry failed tests...

Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
41041	38358	0	11	2651	21

⚪ 2025-12-02 15:00:28 UTC ya make is running... (failed tests rerun, try 2)
🟢 2025-12-02 15:19:29 UTC Tests successful.

Ya make output | Test bloat | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
784 (only retried tests)	767	0	0	1	16

🟢 2025-12-02 15:19:38 UTC Build successful.
🟢 2025-12-02 15:19:54 UTC ydbd size 2.3 GiB changed* by +3.5 KiB, which is < 100.0 KiB vs stable-25-3: OK

ydbd size dash	stable-25-3: 792de81	merge: 83b675d	diff	diff %
ydbd size	2 442 856 200 Bytes	2 442 859 816 Bytes	+3.5 KiB	+0.000%
ydbd stripped size	522 851 944 Bytes	522 853 032 Bytes	+1.1 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]

⚪ 2025-12-02 12:40:27 UTC Pre-commit check linux-x86_64-release-asan for 83b675d has started.
⚪ 2025-12-02 12:40:30 UTC Artifacts will be uploaded here
⚪ 2025-12-02 12:44:33 UTC ya make is running...
🟡 2025-12-02 15:30:28 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?
18114	17577	0	181	336	20

🟢 2025-12-02 15:31:51 UTC Build successful.
🟢 2025-12-02 15:32:15 UTC ydbd size 3.8 GiB changed* by +7.4 KiB, which is < 100.0 KiB vs stable-25-3: OK

ydbd size dash	stable-25-3: 792de81	merge: 83b675d	diff	diff %
ydbd size	4 065 943 400 Bytes	4 065 951 016 Bytes	+7.4 KiB	+0.000%
ydbd stripped size	1 514 825 888 Bytes	1 514 829 184 Bytes	+3.2 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}