feat: add save and send functionality for user message

Adds a "Save" button to the edit message form in Playground, allowing users to save changes without immediately submitting them. This also introduces a new `isSend` flag to the `onEditFormSubmit` prop, enabling developers to control whether a message should be sent immediately or saved for later submission. This enhances flexibility and user control during the message editing process.

src/components/Common/Playground/Message.tsx

@@ -29,7 +29,7 @@ type Props = {
   currentMessageIndex: number
   totalMessages: number
   onRengerate: () => void
-  onEditFormSubmit: (value: string) => void
+  onEditFormSubmit: (value: string, isSend: boolean) => void
   isProcessing: boolean
   webSearch?: {}
   isSearchingInternet?: boolean