GO-3587 Introduce gallery index cache

[KirillSto]

https://linear.app/anytype/issue/GO-3587/add-cache-on-gallerydownloadindex

• add gallery index cache
• remove migration dashboard logic
• move builtinobjects service to gallery service

[github-actions]

New Coverage	50.9% of statements
Patch Coverage	53.9% of changed statements (138/256)

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^{Coverage provided by https://github.com/seriousben/go-patch-cover-action}

[github-actions]

	🟢 SMOKE-TEST PASSED
Tests	✔️ 8 tests run
Summary	🟢 8 passed; 🟡 0 skipped
Duration	🕐 13 minutes, 2 seconds
Testomat.io Report	📊 Run #1b3120d4
Job	🗂️ Smoke Tests / smoke-test
Operating System	🖥️ Linux X64

✅ Passed Tests (8)

• Revoking an invite link (3 minutes, 7 seconds)
• User cancels their join request (1 minute, 24 seconds)
• User deletes the space and rejoins later (1 minute, 38 seconds)
• Owner changes the rights of a user from Viewer to Editor (1 minute, 48 seconds)
• Owner approves a join request with Editor permissions (1 minute, 30 seconds)
• Owner declines a join request (1 minute, 8 seconds)
• Owner removes a participant from the space (1 minute, 22 seconds)
• Sync on staging nodes (1 minute, 1 seconds)