style: DMs only take up 80% of screen width

DMs now take up only 80% of the available screen width so it looks much
more like iMessages.

Closes: #286
Changelog-Changed: Make DMs only take up 80% of screen width

damus/Views/DMView.swift

@@ -10,25 +10,28 @@ import SwiftUI
 struct DMView: View {
     let event: NostrEvent
     let damus_state: DamusState
-    
+
     var is_ours: Bool {
         event.pubkey == damus_state.pubkey
     }
-    
+
     var body: some View {
         HStack {
             if is_ours {
-                Spacer()
+                Spacer(minLength: UIScreen.main.bounds.width * 0.2)
             }
-            
+
             let should_show_img = should_show_images(contacts: damus_state.contacts, ev: event, our_pubkey: damus_state.pubkey)
-            
+
             NoteContentView(privkey: damus_state.keypair.privkey, event: event, profiles: damus_state.profiles, previews: damus_state.previews, show_images: should_show_img, artifacts: .just_content(event.get_content(damus_state.keypair.privkey)), size: .normal)
                 .foregroundColor(is_ours ? Color.white : Color.primary)
                 .padding(10)
                 .background(is_ours ? Color.accentColor : Color.secondary.opacity(0.15))
                 .cornerRadius(8.0)
                 .tint(is_ours ? Color.white : Color.accentColor)
+            if !is_ours {
+                Spacer(minLength: UIScreen.main.bounds.width * 0.2)
+            }
         }
     }
 }