fix(chat): repair inconsistent quote escaping in edit_diagram JSON

When the LLM generates edit_diagram tool calls, it sometimes produces
inconsistent quote escaping in XML attributes within JSON strings.
For example: y="-20\" instead of y=\"-20\"

This causes JSON parsing to fail, and jsonrepair cannot fix this pattern.

Added pre-processing regex to detect and fix cases where the opening
quote is unescaped but the closing quote is escaped in attribute values.

app/api/chat/route.ts

@@ -473,6 +473,13 @@ ${userInputText}
                         inputToRepair = inputToRepair.replace(/:=/g, ": ")
                         // Fix `= "` instead of `: "`
                         inputToRepair = inputToRepair.replace(/=\s*"/g, ': "')
+                        // Fix inconsistent quote escaping in XML attributes within JSON strings
+                        // Pattern: attribute="value\" where opening quote is unescaped but closing is escaped
+                        // Example: y="-20\" should be y=\"-20\"
+                        inputToRepair = inputToRepair.replace(
+                            /(\w+)="([^"]*?)\\"/g,
+                            '$1=\\"$2\\"',
+                        )
                     }
                     // Use jsonrepair to fix truncated JSON
                     const repairedInput = jsonrepair(inputToRepair)

components/chat-input.tsx

@@ -160,9 +160,6 @@ interface ChatInputProps {
     onModelSelect?: (modelId: string | undefined) => void
     showUnvalidatedModels?: boolean
     onConfigureModels?: () => void
-    // Focus control props
-    shouldFocus?: boolean
-    onFocused?: () => void
 }
 
 export function ChatInput({
@@ -182,8 +179,6 @@ export function ChatInput({
     onModelSelect = () => {},
     showUnvalidatedModels = false,
     onConfigureModels = () => {},
-    shouldFocus = false,
-    onFocused,
 }: ChatInputProps) {
     const dict = useDictionary()
     const {
@@ -197,19 +192,6 @@ export function ChatInput({
     const textareaRef = useRef<HTMLTextAreaElement>(null)
     const fileInputRef = useRef<HTMLInputElement>(null)
     const [isDragging, setIsDragging] = useState(false)
-
-    // Focus the textarea when shouldFocus becomes true
-    // Use setTimeout to ensure focus happens after drawio iframe settles
-    useEffect(() => {
-        if (shouldFocus) {
-            const timer = setTimeout(() => {
-                textareaRef.current?.focus()
-                onFocused?.()
-            }, 150)
-            return () => clearTimeout(timer)
-        }
-    }, [shouldFocus, onFocused])
-
     const [showHistory, setShowHistory] = useState(false)
     const [showUrlDialog, setShowUrlDialog] = useState(false)
     const [isExtractingUrl, setIsExtractingUrl] = useState(false)

components/chat-panel.tsx

@@ -173,7 +173,6 @@ export default function ChatPanel({
     const [dailyTokenLimit, setDailyTokenLimit] = useState(0)
     const [tpmLimit, setTpmLimit] = useState(0)
     const [minimalStyle, setMinimalStyle] = useState(false)
-    const [shouldFocusInput, setShouldFocusInput] = useState(false)
 
     // Restore input from sessionStorage on mount (when ChatPanel remounts due to key change)
     useEffect(() => {
@@ -857,7 +856,6 @@ export default function ChatPanel({
 
         // Clear UI state (can't use syncUIWithSession here because we also need to clear files)
         setMessages([])
-        setInput("")
         clearDiagram()
         setDiagramHistory([])
         handleFileChange([]) // Use handleFileChange to also clear pdfData
@@ -872,9 +870,6 @@ export default function ChatPanel({
 
         // Clear URL param to show blank state
         router.replace(window.location.pathname, { scroll: false })
-
-        // After starting a fresh chat, move focus back to the chat input
-        setShouldFocusInput(true)
     }, [
         clearDiagram,
         handleFileChange,
@@ -1301,8 +1296,6 @@ export default function ChatPanel({
                     onModelSelect={modelConfig.setSelectedModelId}
                     showUnvalidatedModels={modelConfig.showUnvalidatedModels}
                     onConfigureModels={() => setShowModelConfigDialog(true)}
-                    shouldFocus={shouldFocusInput}
-                    onFocused={() => setShouldFocusInput(false)}
                 />
             </footer>