Avoid showing reboost alert for pubkey user

Closes: #337
Changelog-Fixed: Don't show report alert if logged in as a pubkey

damus/Models/DamusState.swift

@@ -22,6 +22,11 @@ struct DamusState {
     var pubkey: String {
         return keypair.pubkey
     }
+
+    var is_privkey_user: Bool {
+        keypair.privkey != nil
+    }
+
     
     static var empty: DamusState {
         return DamusState.init(pool: RelayPool(), keypair: Keypair(pubkey: "", privkey: ""), likes: EventCounter(our_pubkey: ""), boosts: EventCounter(our_pubkey: ""), contacts: Contacts(our_pubkey: ""), tips: TipCounter(our_pubkey: ""), profiles: Profiles(), dms: DirectMessagesModel(), previews: PreviewCache())

damus/Views/ActionBar/EventActionBar.swift

@@ -41,7 +41,7 @@ struct EventActionBar: View {
                 EventActionButton(img: "arrow.2.squarepath", col: bar.boosted ? Color.green : nil) {
                     if bar.boosted {
                         notify(.delete, bar.our_boost)
-                    } else {
+                    } else if damus_state.is_privkey_user {
                         self.confirm_boost = true
                     }
                 }.overlay {