fix: correct chat input cursor behavior when content is scrollable

web/screens/Thread/ThreadCenterPanel/ChatInput/RichTextEditor.tsx

@@ -90,10 +90,10 @@
           // Match bold text pattern *text*
           const boldMatches = [...text.matchAll(/(\*.*?\*)/g)] // Find bold patterns
           boldMatches.forEach((match) => {
             const startOffset = match.index + 1 || 0
             const length = match[0].length - 2
 
             ranges.push({
               anchor: { path: [...path, childIndex], offset: startOffset },
               focus: {
                 path: [...path, childIndex],
@@ -113,10 +113,10 @@
           // Match bold text pattern **text**
           const boldMatches = [...text.matchAll(/(\*\*.*?\*\*)/g)] // Find bold patterns
           boldMatches.forEach((match) => {
             const startOffset = match.index + 2 || 0
             const length = match[0].length - 4
 
             ranges.push({
               anchor: { path: [...path, childIndex], offset: startOffset },
               focus: {
                 path: [...path, childIndex],
@@ -139,32 +139,32 @@
 
           if (startMatch) {
             // If it's the start of a code block, store the language
             currentLanguage.current = startMatch[1] || 'plaintext'
           } else if (endMatch) {
             // Reset language when code block ends
             currentLanguage.current = 'plaintext'
           } else if (currentLanguage.current !== 'plaintext') {
             // Highlight entire code line if in a code block
             const leadingSpaces = text.match(/^\s*/)?.[0] ?? '' // Capture leading spaces
             const codeContent = text.trimStart() // Remove leading spaces for highlighting
 
             let highlighted = ''
             highlighted = hljs.highlightAuto(codeContent).value
             try {
               highlighted = hljs.highlight(codeContent, {
                 language:
                   currentLanguage.current.length > 1
                     ? currentLanguage.current
                     : 'plaintext',
               }).value
             } catch (err) {
               highlighted = hljs.highlight(codeContent, {
                 language: 'javascript',
               }).value
             }
 
             const parser = new DOMParser()
             const doc = parser.parseFromString(highlighted, 'text/html')
 
             let slateTextIndex = 0
 
@@ -269,6 +269,10 @@
         ? '100px'
         : '40px'
       textareaRef.current.style.height = textareaRef.current.scrollHeight + 'px'
+      textareaRef.current?.scrollTo({
+        top: textareaRef.current.scrollHeight,
+        behavior: 'instant',
+      })
       textareaRef.current.style.overflow =
         textareaRef.current.clientHeight >= 390 ? 'auto' : 'hidden'
     }