[feature] add support for receiving federated status edits (#3597)

* add support for extracting Updated field from Statusable implementers

* add support for status edits in the database, and update status dereferencer to handle them

* remove unused AdditionalInfo{}.CreatedAt

* remove unused AdditionalEmojiInfo{}.CreatedAt

* update new mention creation to use status.UpdatedAt

* remove mention.UpdatedAt, fixes related to NewULIDFromTime() change

* add migration to remove Mention{}.UpdatedAt field

* add migration to add the StatusEdit{} table

* start adding tests, add delete function for status edits

* add more of status edit migrations, fill in more of the necessary edit delete functionality

* remove unused function

* allow generating gotosocial compatible ulid via CLI with `go run ./cmd/gen-ulid`

* add StatusEdit{} test models

* fix new statusedits sql

* use model instead of table name

* actually remove the Mention.UpdatedAt field...

* fix tests now new models are added, add more status edit DB tests

* fix panic wording

* add test for deleting status edits

* don't automatically set `updated_at` field on updated statuses

* flesh out more of the dereferencer status edit tests, ensure updated at field set on outgoing AS statuses

* remove media_attachments.updated_at column

* fix up more tests, further complete the dereferencer status edit tests

* update more status serialization tests not expecting 'updated' AS property

* gah!! json serialization tests!!

* undo some gtscontext wrapping changes

* more serialization test fixing 🥲

* more test fixing, ensure the edit.status_id field is actually set 🤦

* fix status edit test

* grrr linter

* add edited_at field to apimodel status

* remove the choice of paging on the timeline public filtered test (otherwise it needs updating every time you add statuses ...)

* ensure that status.updated_at always fits chronologically

* fix more serialization tests ...

* add more code comments

* fix envparsing

* update swagger file

* properly handle media description changes during status edits

* slight formatting tweak

* code comment

internal/api/model/content.go

@@ -19,7 +19,6 @@ package model
 
 import (
 	"io"
-	"time"
 
 	"github.com/superseriousbusiness/gotosocial/internal/storage"
 )
@@ -30,8 +29,6 @@ type Content struct {
 	ContentType string
 	// ContentLength in bytes
 	ContentLength int64
-	// Time when the content was last updated.
-	ContentUpdated time.Time
 	// Actual content
 	Content io.ReadCloser
 	// Resource URL to forward to if the file can be fetched from the storage directly (e.g signed S3 URL)