Add saved drafts to posts, replies, and DMs

Changelog-Added: Save drafts to posts, replies and DMs
Closes: #582

damus/Models/HomeModel.swift

@@ -52,15 +52,18 @@ class HomeModel: ObservableObject {
     @Published var events: [NostrEvent] = []
     @Published var loading: Bool = false
     @Published var signal: SignalModel = SignalModel()
+    @Published var drafts_model: DraftsModel
 
     init() {
         self.damus_state = DamusState.empty
         self.dms = DirectMessagesModel(our_pubkey: damus_state.pubkey)
+        self.drafts_model = DraftsModel()
     }
 
     init(damus_state: DamusState) {
         self.damus_state = damus_state
         self.dms = DirectMessagesModel(our_pubkey: damus_state.pubkey)
+        self.drafts_model = DraftsModel()
     }
 
     var pool: RelayPool {