fix: index schema sync race

[Enjection]

Changelog entry

...

Changelog category

• New feature
• Experimental feature
• Improvement
• Performance improvement
• User Interface
• Bugfix
• Backward incompatible change
• Documentation (changelog entry is not required)
• Not for changelog (changelog entry is not required)

Description for reviewers

...

[github-actions]

🟢 2025-11-12 09:38:44 UTC The validation of the Pull Request description is successful.

[Copilot]

Pull Request Overview

This PR fixes a race condition in schema version synchronization for index implementation tables during CDC (Change Data Capture) continuous backup operations.

Key Changes:

• Removed unconditional table->AlterVersion += 1 at the start and replaced with conditional logic based on table type and operation context
• Enhanced continuous backup detection for index implementation tables by checking parent table's CDC streams
• Implemented version synchronization logic that prevents version drift between parent tables, index entities, and index implementation tables using Max() to handle race conditions

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[CyberROFL]

А тест будет?

[CyberROFL]

@Enjection прилинкуй issue

[Enjection]

А тест будет?

Нет. Непонятно как правильно это потестить, у нас сейчас в тестах нельзя поменять порядок операций в SS вручную. Есть некоторые мысли как научиться, но это приключение не на 5 минут.

[github-actions]

⚪ 2025-11-12 11:58:57 UTC Pre-commit check linux-x86_64-relwithdebinfo for c202ebf has started.
⚪ 2025-11-12 11:59:13 UTC Artifacts will be uploaded here
⚪ 2025-11-12 12:01:32 UTC ya make is running...
🟡 2025-11-12 13:34:04 UTC Some tests failed, follow the links below. Going to retry failed tests...

Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
39371	36538	0	3	2800	30

⚪ 2025-11-12 13:34:17 UTC ya make is running... (failed tests rerun, try 2)
🟢 2025-11-12 13:47:09 UTC Tests successful.

Ya make output | Test bloat | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
78 (only retried tests)	60	0	0	0	18

🟢 2025-11-12 13:47:16 UTC Build successful.
🟢 2025-11-12 13:47:37 UTC ydbd size 2.3 GiB changed* by +9.5 KiB, which is < 100.0 KiB vs main: OK

ydbd size dash	main: 8de3d06	merge: c202ebf	diff	diff %
ydbd size	2 441 061 856 Bytes	2 441 071 552 Bytes	+9.5 KiB	+0.000%
ydbd stripped size	519 224 080 Bytes	519 226 192 Bytes	+2.1 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]

⚪ 2025-11-12 11:59:01 UTC Pre-commit check linux-x86_64-release-asan for c202ebf has started.
⚪ 2025-11-12 11:59:19 UTC Artifacts will be uploaded here
⚪ 2025-11-12 12:01:33 UTC ya make is running...
🟡 2025-11-12 13:57:37 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?
15750	15247	0	244	230	29

🟢 2025-11-12 13:57:46 UTC Build successful.
🟢 2025-11-12 13:58:13 UTC ydbd size 3.8 GiB changed* by +6.8 KiB, which is < 100.0 KiB vs main: OK

ydbd size dash	main: 1b58af3	merge: c202ebf	diff	diff %
ydbd size	4 086 822 904 Bytes	4 086 829 816 Bytes	+6.8 KiB	+0.000%
ydbd stripped size	1 517 152 488 Bytes	1 517 154 728 Bytes	+2.2 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}