* Advertise rich text formats, support content_type field
* Update JSON in instance patch tests
* Replace format with content_type everywhere
* update migration to work with both pg and sqlite
* regenerate swagger docs
* update instance serialization + tests
* fix up
* learn to code tobi please, i'm begging you
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Co-authored-by: tsmethurst <tobi.smethurst@protonmail.com>
A note on when we should set data structures linked to objects in the database to use the
bun nullzero tag -- this should only be done if the member type is a pointer, or if the
this primitive type is literally invalid with an empty value (e.g. media IDs which when
empty signifies a null database value, compared to say an account note which when empty
could mean either an empty note OR null database value).
Obviously it is a little more complex than this in practice, but keep it in mind!