Remove unused virtual actors and related logic

[snaury]

Changelog entry

...

Changelog category

• Not for changelog (changelog entry is not required)

Description for reviewers

Virtual actors (where events implement logic instead of actor subclasses) ended up not being used. Removing them gets rid of an unnecessary condition in the event handler.

[github-actions]

🟢 2025-03-11 09:21:48 UTC The validation of the Pull Request description is successful.

[github-actions]

⚪ 2025-03-11 09:21:57 UTC Pre-commit check linux-x86_64-relwithdebinfo for c5429fd has started.
⚪ 2025-03-11 09:22:12 UTC Artifacts will be uploaded here
⚪ 2025-03-11 09:25:35 UTC ya make is running...
🔴 2025-03-11 09:40:43 UTC Build failed, see the logs. Also see fail summary

[github-actions]

⚪ 2025-03-11 09:22:11 UTC Pre-commit check linux-x86_64-release-asan for c5429fd has started.
⚪ 2025-03-11 09:22:27 UTC Artifacts will be uploaded here
⚪ 2025-03-11 09:25:44 UTC ya make is running...
🔴 2025-03-11 09:42:05 UTC Build failed, see the logs. Also see fail summary

[github-actions]

⚪ 2025-03-11 10:03:09 UTC Pre-commit check linux-x86_64-release-asan for d1deaf1 has started.
⚪ 2025-03-11 10:03:25 UTC Artifacts will be uploaded here
⚪ 2025-03-11 10:06:42 UTC ya make is running...
🟡 2025-03-11 11:53:48 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?
14157	13900	0	206	14	37

⚪ 2025-03-11 11:55:43 UTC ya make is running... (failed tests rerun, try 2)
🟡 2025-03-11 12:09:02 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?
360 (only retried tests)	238	0	81	8	33

⚪ 2025-03-11 12:09:13 UTC ya make is running... (failed tests rerun, try 3)
🟡 2025-03-11 12:23:23 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?
201 (only retried tests)	114	0	52	4	31

🟢 2025-03-11 12:23:37 UTC Build successful.
🟢 2025-03-11 12:24:13 UTC ydbd size 3.7 GiB changed* by -312.8 KiB, which is <= 0 Bytes vs main: OK

ydbd size dash	main: 4880f2d	merge: d1deaf1	diff	diff %
ydbd size	3 998 881 392 Bytes	3 998 561 048 Bytes	-312.8 KiB	-0.008%
ydbd stripped size	1 389 593 896 Bytes	1 389 535 848 Bytes	-56.7 KiB	-0.004%

^{*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]

⚪ 2025-03-11 10:05:05 UTC Pre-commit check linux-x86_64-relwithdebinfo for d1deaf1 has started.
⚪ 2025-03-11 10:05:19 UTC Artifacts will be uploaded here
⚪ 2025-03-11 10:08:27 UTC ya make is running...
🟡 2025-03-11 11:41:40 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?
28636	26042	0	4	2474	116

⚪ 2025-03-11 11:45:01 UTC ya make is running... (failed tests rerun, try 2)
🟢 2025-03-11 11:59:21 UTC Tests successful.

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

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
172 (only retried tests)	67	0	0	0	105

🟢 2025-03-11 11:59:33 UTC Build successful.
🟢 2025-03-11 11:59:53 UTC ydbd size 2.1 GiB changed* by -217.3 KiB, which is <= 0 Bytes vs main: OK

ydbd size dash	main: 4880f2d	merge: d1deaf1	diff	diff %
ydbd size	2 296 125 704 Bytes	2 295 903 152 Bytes	-217.3 KiB	-0.010%
ydbd stripped size	480 730 208 Bytes	480 682 016 Bytes	-47.1 KiB	-0.010%

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