keep message drafts on room switches

this is for you courge

lib/helpers/extensions/with_latest_edit.dart

@@ -0,0 +1,20 @@
+import "package:nexus/models/event.dart";
+import "package:nexus/models/room.dart";
+
+extension WithLatestEdit on Room {
+  Event? withLatestEdit(int rowId) {
+    final event = events[rowId];
+    if (event == null) return null;
+
+    final edited = event.lastEditRowId == 0
+        ? null
+        : events[event.lastEditRowId];
+
+    return edited == null
+        ? event
+        : event.copyWith(
+            content: edited.content,
+            localContent: edited.localContent,
+          );
+  }
+}