feat: add OpenRouter support and fix input disabling

- Add OpenRouter provider support with @openrouter/ai-sdk-provider
- Fix input not disabling during 'submitted' state for fast providers
- Apply disable logic to all interactive elements (textarea, buttons, handlers)
- Clean up env.example by removing model examples and separator blocks
- Upgrade zod to v4.1.12 for compatibility with ollama-ai-provider-v2
- Add debug logging for status changes in chat components

components/chat-panel.tsx

@@ -133,9 +133,15 @@ Please retry with an adjusted search pattern or use display_diagram if retries a
         }
     }, [messages]);
 
+    // Debug: Log status changes
+    useEffect(() => {
+        console.log('[ChatPanel] Status changed to:', status);
+    }, [status]);
+
     const onFormSubmit = async (e: React.FormEvent<HTMLFormElement>) => {
         e.preventDefault();
-        if (input.trim() && status !== "streaming") {
+        const isProcessing = status === "streaming" || status === "submitted";
+        if (input.trim() && !isProcessing) {
             try {
                 // Fetch chart data before sending message
                 let chartXml = await onFetchChart();