fix(backend): handle relay-delivered Announce activities correctly

[sinoru]

What

リレーアクター経由で届いたAnnounceアクティビティを通常のRenoteと区別し、内包された元ノートをノートストリームに直接公開するように変更しました。

Changed the handling of Announce activities from relay actors so that the inner note is published directly to the notes stream, instead of being treated as a regular Renote.

Why

リレー経由で配信されたノートはリレーアクターのAnnounceで包まれているため、既存のロジックではRenoteとして表示されてしまう問題がありました。

Notes delivered through relays are wrapped in an Announce activity by the relay actor, causing them to appear as Renotes of the original instead of standalone notes.

Fix #11056

Additional info (optional)

リレーアクターの判定は、アクターのinboxまたはsharedInboxを承認済みリレーのエントリと照合して行います。

Relay actor detection works by matching the actor's inbox or sharedInbox against accepted relay entries.

Checklist

• Read the contribution guide
• Test working in a local environment
• (If needed) Add story of storybook
• (If needed) Update CHANGELOG.md
• (If possible) Add tests

[codecov]

Codecov Report

❌ Patch coverage is 17.24138% with 24 lines in your changes missing coverage. Please review.
✅ Project coverage is 63.63%. Comparing base (8e536eb) to head (0eb63f9).
⚠️ Report is 1 commits behind head on develop.

Files with missing lines	Patch %	Lines
packages/backend/src/core/RelayService.ts	29.41%	12 Missing ⚠️
...ges/backend/src/core/activitypub/ApInboxService.ts	0.00%	12 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #17308      +/-   ##
===========================================
- Coverage    63.64%   63.63%   -0.02%     
===========================================
  Files         1162     1162              
  Lines       116551   116575      +24     
  Branches      8456     8457       +1     
===========================================
- Hits         74181    74179       -2     
- Misses       40165    40211      +46     
+ Partials      2205     2185      -20     

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[github-actions]

このPRによるapi.jsonの差分
差分はありません。
Get diff files from Workflow Page

[github-actions]

Backend memory usage comparison

Before GC

Metric	base (MB)	head (MB)	Diff (MB)	Diff (%)
VmRSS	315.09 MB	320.32 MB	+5.22 MB	+1.65%
VmHWM	315.09 MB	320.32 MB	+5.22 MB	+1.65%
VmSize	23108.72 MB	23114.74 MB	+6.02 MB	+0.02%
VmData	1378.82 MB	1385.61 MB	+6.79 MB	+0.49%

After GC

Metric	base (MB)	head (MB)	Diff (MB)	Diff (%)
VmRSS	315.10 MB	320.32 MB	+5.22 MB	+1.65%
VmHWM	315.10 MB	320.32 MB	+5.22 MB	+1.65%
VmSize	23108.72 MB	23114.82 MB	+6.10 MB	+0.02%
VmData	1378.82 MB	1385.69 MB	+6.87 MB	+0.49%

After Request

Metric	base (MB)	head (MB)	Diff (MB)	Diff (%)
VmRSS	315.57 MB	320.60 MB	+5.03 MB	+1.59%
VmHWM	315.57 MB	320.60 MB	+5.03 MB	+1.59%
VmSize	23108.88 MB	23114.82 MB	+5.93 MB	+0.02%
VmData	1378.98 MB	1385.53 MB	+6.54 MB	+0.47%

See workflow logs for details

[syuilo]

🙏