[Suggestion] Implement sounds routing (upload, list, detail, voting)

[Wikijito7]

Is your feature request related to a problem? Please describe.
The README marks "Sounds routing" as TODO. The web frontend (ecibot-web) already has an audio upload page (/app/audio-request) and audio detail/list pages planned, but there are no backend endpoints to support them.

Describe the solution you'd like
Implement the following API endpoints under the sounds routing:

• GET /sounds — List all sounds (with pagination, filters for pending/approved)
• GET /sound/{id} — Get sound details (name, file URL, uploader, votes)
• POST /sound — Upload a new sound (multipart audio file + metadata)
• PUT /sound/{id} — Update sound metadata (name, etc.)
• DELETE /sound/{id} — Delete a sound
• POST /sound/{id}/vote — Vote on a sound (thumbs up/down)
• GET /user/sounds — List sounds uploaded by the authenticated user

Describe alternatives you've considered

• Embedding audio file serving through a separate static file server
• Using the Discord bot as a proxy for audio operations

Additional context
The web frontend needs at minimum:

• Audio upload with drag & drop
• Pending sounds list with voting
• Sound detail page with audio player

Media
N/A