feat: add in lexicons for all the xrpc calls.

[purifetchi]

No description provided.

[mary-ext]

I think you can shorten a lot of these field names since the object names already makes it clear what it's about, e.g. oekakiRecordKey to recordKey/rkey.

I'd probably recommend only returning an AT-URI rather than both (though it does come at the expense of having to fish it out every time you need it for something).

but if you're going this route, you should probably set the string's format to record-key, I don't remember if the JSON schema has it.

[purifetchi]

@mary-ext applied your hints about shortening the names of some of the field names. could you check and say whether they look alright or not?

[mary-ext]

sgtm, could move the did and handle field to an author object so you can extend more on it later on