Dashboard: Remove unused assets (#6948)

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## PR-Codex overview
This PR focuses on the deletion of numerous asset files from the `apps/dashboard/public` directory and an update to the `logUnusedAssets.ts` script to adjust how asset file names are checked within the content.

### Detailed summary
- Deleted multiple asset files from `apps/dashboard/public/logos`, `apps/dashboard/public/assets`, and `apps/dashboard/public/assets/community/gallery`.
- Modified the `logUnusedAssets.ts` script:
  - Changed the condition to check for asset file names to include a leading slash: `if (content.includes(`/${assetFileName.name}`))`.

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Author: MananTank