* Avoid showing system message content in history
* Bug in schema (wrong video_content dependency)
* Add/replace video-embeds
* Rephrase odelia to avoid "compulsory color schtick"

also:
* sort the globs
* add a vid

Also:

* Do not crash when session has no history
* Tv-frame style for embeds

Allow img tag from media libraries
(avoid img hallucinations)

decrease hallucinated img tags

Also display flash messages if needed

`prompt.txt` template also contains (via jinja)

* chat.schema.json
* chat-example.json
* in the future, there will be patient-specific variants

`/img` is an image generator (handy)

Updates `static/slides.json` (copies backup `archive/`)