[feature] More consistent API error handling (#637)

* update templates

* start reworking api error handling

* update template

* return AP status at web endpoint if negotiated

* start making api error handling much more consistent

* update account endpoints to new error handling

* use new api error handling in admin endpoints

* go fmt ./...

* use api error logic in app

* use generic error handling in auth

* don't export generic error handler

* don't defer clearing session

* user nicer error handling on oidc callback handler

* tidy up the sign in handler

* tidy up the token handler

* use nicer error handling in blocksget

* auth emojis endpoint

* fix up remaining api endpoints

* fix whoopsie during login flow

* regenerate swagger docs

* change http error logging to debug

internal/processing/media/media.go

@@ -34,7 +34,7 @@ import (
 // Processor wraps a bunch of functions for processing media actions.
 type Processor interface {
 	// Create creates a new media attachment belonging to the given account, using the request form.
-	Create(ctx context.Context, account *gtsmodel.Account, form *apimodel.AttachmentRequest) (*apimodel.Attachment, error)
+	Create(ctx context.Context, account *gtsmodel.Account, form *apimodel.AttachmentRequest) (*apimodel.Attachment, gtserror.WithCode)
 	// Delete deletes the media attachment with the given ID, including all files pertaining to that attachment.
 	Delete(ctx context.Context, mediaAttachmentID string) gtserror.WithCode
 	// GetFile retrieves a file from storage and streams it back to the caller via an io.reader embedded in *apimodel.Content.