docs(README): update custom samples and clarify endpoint configuration

Update README with corrected typo in "Custom Samples" section and provide additional comments for setting custom API endpoints and configuring prompts. Highlight changes for markdown transformation and editor updates.

README.md

@@ -136,13 +136,15 @@ const BubbleMenu: PromptAction[] = [
 ];
 ```
 
-Custom Smamples:
+Custom Samples:
 
 
 ```tsx
+// custom api endpoint
 const actionExecutor: AiActionExecutor = new AiActionExecutor();
-actionExecutor.setEndpointUrl("/api/chat");
+actionExecutor.setEndpointUrl("/api/chat"); 
 
+// custom prompts 
 const instance = PromptsManager.getInstance();
 const map = customSlashActions?.map((action) => {
   return {
@@ -159,10 +161,12 @@ const map = customSlashActions?.map((action) => {
   };
 }) || [];
 
+// set  prompts group to default article group
 instance.updateActionsMap("article", ArticlePrompts.concat(map));
 
 const editor = useEditor({
   extensions: setupExtensions(instance, actionExecutor).concat([
+    /// configure for copy and paste
     Markdown.configure({
       transformPastedText: true,
       transformCopiedText: false,
@@ -177,6 +181,7 @@ const editor = useEditor({
   },
   onUpdate: ({ editor }) => {
     if (onChange) {
+      /// update markdown
       const schema = editor.state.schema;
       try {
         const serializer = DOMSerializer.fromSchema(schema);