Add post editing capability (#2828)

* Add post editing capability

* Don't try to reprocess already uploaded attachments.
Fixes editing posts with existing media

* Don't mark post edits as modified until editing occurs

* Disable UI for things that can't be edited when editing a post

* Finally convert SFragment to kotlin

* Use api endpoint for fetching status source for editing

* Apply review feedback

app/src/main/java/com/keylesspalace/tusky/receiver/SendStatusBroadcastReceiver.kt

@@ -100,7 +100,8 @@ class SendStatusBroadcastReceiver : BroadcastReceiver() {
                         idempotencyKey = randomAlphanumericString(16),
                         retries = 0,
                         mediaProcessed = mutableListOf(),
-                        null,
+                        language = null,
+                        statusId = null,
                     )
                 )