fix not showing first membership events

lib/widgets/renderers/event.dart

@@ -67,7 +67,7 @@ class EventRenderer extends ConsumerWidget {
             MembershipContent content => switch (event.previousContent) {
               MembershipContent(:final status) =>
                 status == content.status ? null : MembershipRenderer(event),
-              _ => null,
+              _ => MembershipRenderer(event),
             },
 
             AvatarContent() => GenericEventRenderer(Icons.interests, [
@@ -80,12 +80,12 @@ class EventRenderer extends ConsumerWidget {
               Text("created the room"),
             ]),
 
-            PowerLevelsContent() => GenericEventRenderer(Icons.add, [
+            PowerLevelsContent() => GenericEventRenderer(Icons.power, [
               MessageDisplayname(event),
               Text("changed the room's power levels"),
             ]),
 
-            JoinRulesContent() => GenericEventRenderer(Icons.add, [
+            JoinRulesContent() => GenericEventRenderer(Icons.rule, [
               MessageDisplayname(event),
               Text("changed the room's join rules"),
             ]),