EXT-1551. Remove obsolete UsageByActivity sensor from ActorSystem

[va-kuznecov]

cherry-pick from PR (#26188)

Changelog entry

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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

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[github-actions]

⚪ 2025-10-08 16:23:46 UTC Pre-commit check for bf5cb84 has started.
⚪ 2025-10-08 16:26:47 UTC Build linux-x86_64-relwithdebinfo is running...
🔴 2025-10-08 16:38:43 UTC Build failed. see the build logs.
🔴 2025-10-08 16:38:45 UTC Tests run skipped.

[github-actions]

⚪ 2025-10-08 16:27:18 UTC Pre-commit check for bf5cb84 has started.
⚪ 2025-10-08 16:30:32 UTC Build linux-x86_64-release-asan is running...
🔴 2025-10-08 16:33:42 UTC Build failed. see the build logs.
🔴 2025-10-08 16:33:44 UTC Tests run skipped.

[github-actions]

⚪ 2025-10-09 15:35:03 UTC Pre-commit check for 1fc6474 has started.
⚪ 2025-10-09 15:37:56 UTC Build linux-x86_64-release-asan is running...
🟢 2025-10-09 16:28:51 UTC Build successful.
⚪ 2025-10-09 16:29:13 UTC Tests are running...
🔴 2025-10-09 18:54:36 UTC Some tests failed, follow the links below.

Test history | Test log

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
11586	11437	0	31	34	84

🟢 2025-10-09 18:55:19 UTC ydbd size 5.7 GiB changed* by -180.8 KiB, which is <= 0 Bytes vs stream-nb-24-4: OK

ydbd size dash	stream-nb-24-4: 3c9d2dd	merge: 1fc6474	diff	diff %
ydbd size	6 069 761 600 Bytes	6 069 576 488 Bytes	-180.8 KiB	-0.003%
ydbd stripped size	1 519 820 608 Bytes	1 519 782 144 Bytes	-37.6 KiB	-0.003%

^{*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]

⚪ 2025-10-09 15:35:04 UTC Pre-commit check for 1fc6474 has started.
⚪ 2025-10-09 15:38:01 UTC Build linux-x86_64-relwithdebinfo is running...
🟢 2025-10-09 16:51:52 UTC Build successful.
⚪ 2025-10-09 16:52:09 UTC Tests are running...
🔴 2025-10-09 18:20:32 UTC Some tests failed, follow the links below.

Test history | Test log

TESTS	PASSED	ERRORS	FAILED	SKIPPED	MUTED?
16121	14734	0	2	1303	82

🟢 2025-10-09 18:21:20 UTC ydbd size 8.3 GiB changed* by -425.4 KiB, which is <= 0 Bytes vs stream-nb-24-4: OK

ydbd size dash	stream-nb-24-4: 3c9d2dd	merge: 1fc6474	diff	diff %
ydbd size	8 953 520 920 Bytes	8 953 085 264 Bytes	-425.4 KiB	-0.005%
ydbd stripped size	487 449 160 Bytes	487 443 464 Bytes	-5.6 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}