[25-3-1] Reject vector index settings with unknown protobuf fields

[vitalif]

Changelog category

• Not for changelog (changelog entry is not required)

Description for reviewers

Cherry-pick of #30537

[ydbot]

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• Test Size: small, medium, large (default: all)
• Test Targets: any directory path (default: ydb/)
• Sanitizers: ASAN, MSAN, TSAN
• Coredumps: enable for debugging (default: off)
• Additional args: custom ya make arguments

[github-actions]

🟢 2025-12-12 09:18:35 UTC The validation of the Pull Request description is successful.

[github-actions]

⚪ 2025-12-12 09:19:29 UTC Pre-commit check linux-x86_64-relwithdebinfo for 830a5cc has started.
⚪ 2025-12-12 09:20:18 UTC Artifacts will be uploaded here
⚪ 2025-12-12 09:23:50 UTC ya make is running...
🔴 2025-12-12 09:26:16 UTC Build failed, see the logs. Also see fail summary

[github-actions]

⚪ 2025-12-12 09:19:42 UTC Pre-commit check linux-x86_64-release-asan for 830a5cc has started.
⚪ 2025-12-12 09:19:55 UTC Artifacts will be uploaded here
⚪ 2025-12-12 09:23:30 UTC ya make is running...
🔴 2025-12-12 09:25:53 UTC Build failed, see the logs. Also see fail summary

[github-actions]

⚪ 2025-12-12 10:06:26 UTC Pre-commit check linux-x86_64-relwithdebinfo for 3522015 has started.
⚪ 2025-12-12 10:06:40 UTC Artifacts will be uploaded here
⚪ 2025-12-12 10:10:14 UTC ya make is running...
🟡 2025-12-12 11:36:55 UTC Some tests failed, follow the links below. Going to retry failed tests...

Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
40416	37734	0	8	2651	23

⚪ 2025-12-12 11:37:04 UTC ya make is running... (failed tests rerun, try 2)
🟡 2025-12-12 11:55:48 UTC Some tests failed, follow the links below. Going to retry failed tests...

Ya make output | Test bloat | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
637 (only retried tests)	616	0	4	1	16

⚪ 2025-12-12 11:55:51 UTC ya make is running... (failed tests rerun, try 3)
🟢 2025-12-12 12:12:56 UTC Tests successful.

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

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
593 (only retried tests)	580	0	0	1	12

🟢 2025-12-12 12:12:59 UTC Build successful.
🟢 2025-12-12 12:13:24 UTC ydbd size 2.3 GiB changed* by -30.8 MiB, which is <= 0 Bytes vs main: OK

ydbd size dash	main: 7fe9277	merge: 3522015	diff	diff %
ydbd size	2 468 806 360 Bytes	2 436 523 960 Bytes	-30.8 MiB	-1.308%
ydbd stripped size	525 344 608 Bytes	521 181 896 Bytes	-4.0 MiB	-0.792%

^{*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]

⚪ 2025-12-12 10:06:48 UTC Pre-commit check linux-x86_64-release-asan for 3522015 has started.
⚪ 2025-12-12 10:07:02 UTC Artifacts will be uploaded here
⚪ 2025-12-12 10:10:43 UTC ya make is running...
🟡 2025-12-12 12:17:22 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?
17394	16900	0	159	313	22

🟢 2025-12-12 12:17:28 UTC Build successful.
🟢 2025-12-12 12:17:57 UTC ydbd size 3.8 GiB changed* by -75.7 MiB, which is <= 0 Bytes vs main: OK

ydbd size dash	main: 7fe9277	merge: 3522015	diff	diff %
ydbd size	4 134 217 592 Bytes	4 054 796 560 Bytes	-75.7 MiB	-1.921%
ydbd stripped size	1 534 515 928 Bytes	1 510 619 456 Bytes	-22.8 MiB	-1.557%

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