fix: improve VLM validation with bug fixes and i18n

- Fix race condition in pendingValidationRef (reject previous pending validation)
- Fix response format consistency (use streaming for all responses)
- Remove dead code (unused lastRequestRef and ValidationRequest interface)
- Consolidate duplicate types (re-export from validation-schema.ts)
- Add 'success_with_warnings' status for valid diagrams with warnings
- Fix tool card auto-collapse (only collapse once, respect user toggle)
- Set VLM validation default to disabled
- Add i18n support for diagram validation settings (en/zh/ja)
- Mark feature as experimental in settings UI

components/chat-message-display.tsx

@@ -435,11 +435,15 @@ export function ChatMessageDisplay({
                         const toolPart = part as ToolPartLike
                         const { toolCallId, state, input } = toolPart
 
+                        // Auto-collapse on completion, but only if user hasn't manually toggled
                         if (state === "output-available") {
-                            setExpandedTools((prev) => ({
-                                ...prev,
-                                [toolCallId]: false,
-                            }))
+                            setExpandedTools((prev) => {
+                                // Only auto-collapse if not already set (user hasn't interacted)
+                                if (prev[toolCallId] === undefined) {
+                                    return { ...prev, [toolCallId]: false }
+                                }
+                                return prev
+                            })
                         }
 
                         if (

components/chat-panel.tsx

@@ -178,7 +178,7 @@ export default function ChatPanel({
     const [dailyTokenLimit, setDailyTokenLimit] = useState(0)
     const [tpmLimit, setTpmLimit] = useState(0)
     const [minimalStyle, setMinimalStyle] = useState(false)
-    const [vlmValidationEnabled, setVlmValidationEnabled] = useState(true)
+    const [vlmValidationEnabled, setVlmValidationEnabled] = useState(false)
     const [shouldFocusInput, setShouldFocusInput] = useState(false)
 
     // Restore input from sessionStorage on mount (when ChatPanel remounts due to key change)

components/chat/ToolCallCard.tsx

@@ -67,8 +67,8 @@ export function ToolCallCard({
 }: ToolCallCardProps) {
     const callId = part.toolCallId
     const { state, input, output } = part
-    // Default to collapsed if tool is complete, expanded if still streaming
-    const isExpanded = expandedTools[callId] ?? state !== "output-available"
+    // Default to expanded for all states (user can manually collapse if needed)
+    const isExpanded = expandedTools[callId] ?? true
     const toolName = part.type?.replace("tool-", "")
     const isCopied = copiedToolCallId === callId
 

components/chat/ValidationCard.tsx

@@ -19,6 +19,7 @@ export type ValidationStatus =
     | "capturing"
     | "validating"
     | "success"
+    | "success_with_warnings"
     | "failed"
     | "error"
     | "skipped"
@@ -95,7 +96,9 @@ export function ValidationCard({
     const showImproveButton =
         onImproveWithSuggestions &&
         state.result &&
-        (state.status === "success" || state.status === "skipped") &&
+        (state.status === "success" ||
+            state.status === "success_with_warnings" ||
+            state.status === "skipped") &&
         (state.result.issues.length > 0 || state.result.suggestions.length > 0)
 
     const getStatusDisplay = () => {
@@ -124,6 +127,14 @@ export function ValidationCard({
                     color: "text-green-600 bg-green-50",
                     icon: <Check className="h-4 w-4" aria-hidden="true" />,
                 }
+            case "success_with_warnings":
+                return {
+                    label: "Valid with Warnings",
+                    color: "text-amber-600 bg-amber-50",
+                    icon: (
+                        <AlertTriangle className="h-4 w-4" aria-hidden="true" />
+                    ),
+                }
             case "failed":
                 return {
                     label: "Issues Found",

components/settings-dialog.tsx

@@ -90,7 +90,7 @@ function SettingsContent({
     onToggleDarkMode,
     minimalStyle = false,
     onMinimalStyleChange = () => {},
-    vlmValidationEnabled = true,
+    vlmValidationEnabled = false,
     onVlmValidationChange = () => {},
 }: SettingsDialogProps) {
     const dict = useDictionary()
@@ -416,8 +416,8 @@ function SettingsContent({
 
                     {/* VLM Diagram Validation */}
                     <SettingItem
-                        label="Diagram Validation"
-                        description="Use AI vision to validate and improve generated diagrams"
+                        label={dict.settings.diagramValidation}
+                        description={dict.settings.diagramValidationDescription}
                     >
                         <div className="flex items-center gap-2">
                             <Switch
@@ -426,7 +426,9 @@ function SettingsContent({
                                 onCheckedChange={onVlmValidationChange}
                             />
                             <span className="text-sm text-muted-foreground">
-                                {vlmValidationEnabled ? "Enabled" : "Disabled"}
+                                {vlmValidationEnabled
+                                    ? dict.settings.enabled
+                                    : dict.settings.disabled}
                             </span>
                         </div>
                     </SettingItem>