fix: allow Veo model parameters to render in GenerateVideoNode UI

The render guard at line 222 blocked all Gemini-provider models from
rendering parameters, including Veo models. Hoisted the isVeoModel
check to component scope and added the same exception used in the
fetch guard so Veo parameters (aspect ratio, duration, resolution)
display correctly.

Fixes #106

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/components/nodes/ModelParameters.tsx

@@ -82,9 +82,10 @@ function ModelParametersInner({
   // Use stable selector for API keys to prevent unnecessary re-fetches
   const { replicateApiKey, falApiKey, kieApiKey, wavespeedApiKey } = useProviderApiKeys();
 
+  const isVeoModel = modelId?.startsWith("veo-");
+
   // Fetch schema when modelId changes
   useEffect(() => {
-    const isVeoModel = modelId?.startsWith("veo-");
     if (!modelId || (provider === "gemini" && !isVeoModel)) {
       setSchema([]);
       onInputsLoaded?.([]);
@@ -218,8 +219,8 @@ function ModelParametersInner({
       : sortedSchema;
   }, [sortedSchema, useGrid, colCount]);
 
-  // Don't render anything for Gemini or if no model selected
-  if (provider === "gemini" || !modelId) {
+  // Don't render anything for Gemini (except Veo) or if no model selected
+  if ((provider === "gemini" && !isVeoModel) || !modelId) {
     return null;
   }