Expose draft updates to iOS bridge

apps/ios/TeleTuiIOS/Sources/TeleTuiIOSCore/Bridge.swift

@@ -18,6 +18,7 @@ public protocol SessionBridge: Sendable {
     func react(chatId: Int64, messageId: Int64, reaction: String) async throws -> [Reaction]
     func pinnedMessages(chatId: Int64) async throws -> [Message]
     func copyPayload(chatId: Int64, messageId: Int64) async throws -> String
+    func setDraft(chatId: Int64, text: String) async throws
     func downloadPhoto(fileId: Int32) async throws -> DownloadedFile
     func downloadVoice(fileId: Int32) async throws -> DownloadedFile
 }
@@ -204,6 +205,14 @@ public actor FakeSessionBridge: SessionBridge {
         return message.text
     }
 
+    public func setDraft(chatId: Int64, text: String) async throws {
+        let draft = Draft(chatId: chatId, text: text)
+        if let index = chats.firstIndex(where: { $0.id == chatId }) {
+            chats[index].draft = text.isEmpty ? nil : draft
+        }
+        events.append(.draftChanged(draft))
+    }
+
     public func downloadPhoto(fileId: Int32) async throws -> DownloadedFile {
         DownloadedFile(fileId: fileId, path: "/tmp/fake-photo-\(fileId).jpg")
     }

apps/ios/TeleTuiIOS/Sources/TeleTuiIOSCore/UniFfiSessionBridge.swift

@@ -105,6 +105,10 @@ public actor UniFfiSessionBridge: SessionBridge {
         try handle.copyPayload(chatId: chatId, messageId: messageId)
     }
 
+    public func setDraft(chatId: Int64, text: String) async throws {
+        try handle.setDraft(chatId: chatId, text: text)
+    }
+
     public func downloadPhoto(fileId: Int32) async throws -> DownloadedFile {
         try Self.mapDownloadedFile(handle.downloadPhoto(fileId: fileId))
     }

apps/ios/TeleTuiIOS/Sources/TeleTuiIOSCore/ViewModels.swift

@@ -228,6 +228,15 @@ public final class ChatViewModel: ObservableObject {
         }
     }
 
+    public func saveDraft() async {
+        do {
+            try await bridge.setDraft(chatId: chat.id, text: composeText)
+            errorMessage = nil
+        } catch {
+            errorMessage = error.localizedDescription
+        }
+    }
+
     private func replaceMessage(_ message: Message) {
         if let index = messages.firstIndex(where: { $0.id == message.id }) {
             messages[index] = message