Two distinct fixes:
1. Database terminology: Make it crystal clear that generated projects use
CockroachDB in production and PostgreSQL for local dev, while the rdev
platform itself uses PostgreSQL. Updated 15 files across skeleton agents,
component templates, cookbook trees, and platform docs.
2. Video storage: VideoHandler was ignoring vid.Data bytes (already downloaded
by the Gemini adapter with auth) and re-downloading from the provider URL
with a plain GET — which fails because Gemini URLs require API key auth.
Now uses vid.Data first, falls back to downloadURL only for public URLs.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>