fix(backend): update and re-enable Bull Dashboard

[zyoshoka]

What

Bull Dashboard は #14594 で無効化されていましたが Fastify 5 対応のリリースが出ましたので使えるように戻します。

Why

ないと不便ですので

Additional info (optional)

Checklist

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

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 39.75%. Comparing base (15f2e14) to head (c351a10). Report is 3 commits behind head on develop.

Files with missing lines	Patch %	Lines
...ages/backend/src/server/web/ClientServerService.ts	0.00%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #14648 +/- ## =========================================== - Coverage 39.75% 39.75% -0.01% =========================================== Files 1544 1544 Lines 193604 193618 +14 Branches 2561 3537 +976 =========================================== - Hits 76972 76970 -2 + Misses 116069 116053 -16 - Partials 563 595 +32 ```

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[github-actions[bot]]

Thank you for sending us a great Pull Request! 👍 Please regenerate misskey-js type definitions! 🙏

example:

pnpm run build-misskey-js-with-types

[github-actions[bot]]

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

[syuilo]

🙏🏻