Hide Edit Button on Profile Page for the user not logged in w/Private Key

Changelog-Fixed: Hide edit button on profile page when no private key
Closes: #215

damus/Views/EditMetadataView.swift

@@ -174,7 +174,7 @@ struct EditMetadataView: View {
                         Text(String.localizedStringWithFormat("'%@' is an invalid nip05 identifier. It should look like an email.", nip05))
                     }
                 })
-                
+
                 Button("Save") {
                     save()
                     dismiss()

damus/Views/ProfileView.swift

@@ -196,8 +196,10 @@ struct ProfileView: View {
                         follow_state: damus_state.contacts.follow_state(profile.pubkey)
                     )
                 } else {
-                    NavigationLink(destination: EditMetadataView(damus_state: damus_state)) {
-                        EditButton(damus_state: damus_state)
+                    if damus_state.keypair.privkey != nil {
+                        NavigationLink(destination: EditMetadataView(damus_state: damus_state)) {
+                            EditButton(damus_state: damus_state)
+                        }
                     }
                 }