Video epic — deferred follow-ups (webcast embed · ISS liveness · LM-10B · re-uploads)

[chipi]

Split from the now-closed epic #413 (Video & Live Feeds, PRD-031 / RFC-033) so the shipped core can close while these enhancements stay tracked.

Design: PRD-031 · RFC-033.

Deferred follow-ups

• Embed launch webcasts — extend scripts/fetch-launches.ts + the LL2 adapter to capture vidURLs → a webcast_url field, then embed live launch webcasts (currently link-out).
• ISS liveness probe (RFC-033 open Q4) — detect stream-offline instead of always showing the LIVE badge.
• Long March-10B first-booster-recovery clip (CCTV-verified) — needs a long-march-10 fleet entity created first.
• JAXA / others — a few historic clips only exist as re-uploads (noted in the handover); revisit if first-party sources surface.

Core epic (Phases 1 & 2) shipped to main and is CI-green; see #413.