chore: add use window.ENV.BASE_URL as backendOrigin (#205)

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Co-authored-by: Marcus Schiesser <mail@marcusschiesser.de>

templates/components/ui/html/chat/hooks/use-config.ts

@@ -12,7 +12,15 @@ export function useClientConfig(): ChatConfig {
   const [config, setConfig] = useState<ChatConfig>();
 
   const backendOrigin = useMemo(() => {
-    return chatAPI ? new URL(chatAPI).origin : "";
+    if (chatAPI) {
+      return new URL(chatAPI).origin;
+    } else {
+      if (typeof window !== "undefined") {
+        // Use BASE_URL from window.ENV
+        return (window as any).ENV?.BASE_URL || "";
+      }
+      return "";
+    }
   }, [chatAPI]);
 
   const configAPI = `${backendOrigin}/api/chat/config`;