feat: Added defaultOpen Attribute for iframe (#302)

* feat: Added defaultOpen Attribute for iframe

This commit introduces a new attribute `defaultOpen` for the iframe created in `iframe.js`. The `defaultOpen` attribute allows the iframe to be visible by default when the page loads. This new feature enhances the user experience by providing an option to display the chatbot window immediately after the page is loaded, without requiring user interaction.

* Update iframe.js

code standard

client/public/js/iframe.js

@@ -4,6 +4,7 @@ async function embedChatbot() {
   const script = document.getElementById('fastgpt-iframe');
   const botSrc = script?.getAttribute('data-src');
   const primaryColor = script?.getAttribute('data-color') || '#4e83fd';
+  const defaultOpen = script?.getAttribute('data-default-open') === 'true';
   
   if (!botSrc) {
     console.error(`Can't find appid`);
@@ -30,9 +31,9 @@ async function embedChatbot() {
   iframe.title = 'FastGPT Chat Window';
   iframe.id = chatWindowId;
   iframe.src = botSrc;
-
   iframe.style.cssText =
-    'visibility: hidden; border: none; position: fixed; flex-direction: column; justify-content: space-between; box-shadow: rgba(150, 150, 150, 0.2) 0px 10px 30px 0px, rgba(150, 150, 150, 0.2) 0px 0px 0px 1px; bottom: 4rem; right: 1rem; width: 24rem; height: 40rem; max-width: 90vw; max-height: 85vh; border-radius: 0.75rem; display: flex; z-index: 2147483647; overflow: hidden; left: unset; background-color: #F3F4F6;';
+    'border: none; position: fixed; flex-direction: column; justify-content: space-between; box-shadow: rgba(150, 150, 150, 0.2) 0px 10px 30px 0px, rgba(150, 150, 150, 0.2) 0px 0px 0px 1px; bottom: 4rem; right: 1rem; width: 24rem; height: 40rem; max-width: 90vw; max-height: 85vh; border-radius: 0.75rem; display: flex; z-index: 2147483647; overflow: hidden; left: unset; background-color: #F3F4F6;';
+  iframe.style.visibility = defaultOpen ? 'unset' : 'hidden'; 
  
   document.body.appendChild(iframe);