DM Design Tweaks (#3693)

* dm design tweaks

* adding equatable conformance

* topic will now be shown in DMs

* code suggestion

* updated details

* better check

* code improvement

ElementX/Sources/Other/SwiftUI/Views/AvatarHeaderView.swift

@@ -37,7 +37,14 @@ struct AvatarHeaderView<Footer: View>: View {
          @ViewBuilder footer: @escaping () -> Footer) {
         avatarInfo = .room(room.avatar)
         title = room.name ?? room.id
-        subtitle = room.canonicalAlias
+        
+        if let roomAlias = room.canonicalAlias {
+            subtitle = roomAlias
+        } else if room.isDirect, case let .heroes(heroes) = room.avatar, heroes.count == 1 {
+            subtitle = heroes[0].userID
+        } else {
+            subtitle = nil
+        }
         
         self.avatarSize = avatarSize
         self.mediaProvider = mediaProvider
@@ -193,7 +200,8 @@ struct AvatarHeaderView_Previews: PreviewProvider, TestablePreview {
                                                        avatarURL: .mockMXCAvatar),
                                          canonicalAlias: "#test:matrix.org",
                                          isEncrypted: true,
-                                         isPublic: true),
+                                         isPublic: true,
+                                         isDirect: false),
                              avatarSize: .room(on: .details),
                              mediaProvider: MediaProviderMock(configuration: .init())) {
                 HStack(spacing: 32) {