feat(routes-f): multi-camera angle switcher

[davedumto]

Summary

Manage available camera angles for a stream and current viewer selection.

Requirements

• GET ?stream_id returns { angles: [{ id, label, playback_id }] }
• POST { viewer_id, stream_id, angle_id } stores viewer's choice
• Bundle seed multi-angle streams
• Tests cover list, select, and unknown-angle rejection

Scope Constraint - READ BEFORE STARTING

All files for this task must live inside app/api/routes-f/. This includes the route handler, helpers/utilities, types, and tests. Do NOT modify, import from, or add files to lib/, utils/, types/, components/, or anywhere else outside app/api/routes-f/. If you need shared logic, duplicate it inside your subfolder. Keeping everything scoped to this folder is intentional - it keeps these tasks independent and mergeable in any order.

Product Context

StreamFi is a blockchain-powered live streaming platform. Streamers broadcast via Mux, viewers tip in Stellar XLM/USDC, creators have stream privacy modes (public/unlisted/subscribers-only). Build these issues as practice implementations - use realistic data shapes that match the platform domain, but do not import from the real app code.

[aymide1ee]

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[Georgebingi]

@Georgebingi has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi I'm a full stack developer I'll like to work on this issue because It picks my interest and Ive got experience with similar projects I'll have it solved in 24 hours or less

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[josephchimebuka]

@josephchimebuka has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi GM, I have reviewed this issue and taken the time to understand the requirements, current implementation, and the expected outcome. Based on my analysis, I believe this is something I can successfully handle and contribute to... Kindly assign

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Congratulations, @josephchimebuka! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

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[drips-wave]

This issue has been completed by @josephchimebuka as part of the Stellar Wave Program's 6th Wave 🥳

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