support SHOW CREATE VIEW

[jepett0]

Changelog entry

Changelog category

• Not for changelog (changelog entry is not required)

Description for reviewers

Issues:

• view: show create #16283

Support SHOW CREATE VIEW YQL statement.

[github-actions]

🟢 2025-04-02 12:47:54 UTC The validation of the Pull Request description is successful.

[github-actions]

⚪ 2025-04-02 12:54:41 UTC Pre-commit check linux-x86_64-release-asan for 0f8e472 has started.
⚪ 2025-04-02 12:55:09 UTC Artifacts will be uploaded here
⚪ 2025-04-02 12:58:40 UTC ya make is running...
🟡 2025-04-02 14:11:19 UTC Some tests failed, follow the links below. This fail is not in blocking policy yet Going to retry failed tests...

Test history | Ya make output | Test bloat

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
12688	12558	0	62	34	34

⚪ 2025-04-02 14:12:23 UTC ya make is running... (failed tests rerun, try 2)
🟡 2025-04-02 14:29:28 UTC Some tests failed, follow the links below. This fail is not in blocking policy yet Going to retry failed tests...

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

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
173 (only retried tests)	100	0	32	11	30

⚪ 2025-04-02 14:29:39 UTC ya make is running... (failed tests rerun, try 3)
🟡 2025-04-02 14:42:08 UTC Some tests failed, follow the links below. This fail is not in blocking policy yet

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

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
98 (only retried tests)	31	0	31	6	30

🟢 2025-04-02 14:42:20 UTC Build successful.
🟡 2025-04-02 14:42:50 UTC ydbd size 3.8 GiB changed* by +194.1 KiB, which is >= 100.0 KiB vs main: Warning

ydbd size dash	main: 4d6d062	merge: 0f8e472	diff	diff %
ydbd size	4 123 974 632 Bytes	4 124 173 392 Bytes	+194.1 KiB	+0.005%
ydbd stripped size	1 424 976 488 Bytes	1 424 986 024 Bytes	+9.3 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]

⚪ 2025-04-02 12:56:58 UTC Pre-commit check linux-x86_64-relwithdebinfo for 0f8e472 has started.
⚪ 2025-04-02 12:57:13 UTC Artifacts will be uploaded here
⚪ 2025-04-02 13:00:14 UTC ya make is running...
🟡 2025-04-02 14:07:03 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?
27118	24458	0	7	2543	110

⚪ 2025-04-02 14:09:20 UTC ya make is running... (failed tests rerun, try 2)
🟢 2025-04-02 14:19:41 UTC Tests successful.

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

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
168 (only retried tests)	69	0	0	0	99

🟢 2025-04-02 14:19:53 UTC Build successful.
🟡 2025-04-02 14:20:14 UTC ydbd size 2.2 GiB changed* by +108.5 KiB, which is >= 100.0 KiB vs main: Warning

ydbd size dash	main: 4d6d062	merge: 0f8e472	diff	diff %
ydbd size	2 350 370 736 Bytes	2 350 481 864 Bytes	+108.5 KiB	+0.005%
ydbd stripped size	491 570 208 Bytes	491 572 448 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}

[pnv1]

CLI part LGTM

[CyberROFL]

Тут можно обойтись forward declaration.