fix: add imageUrl validation for img2video mode

When model is set to 'img2video', the imageUrl parameter is required.
This validation was flagged in the Greptile review and is now fixed.

Author: adhikjoshi

apps/sim/app/api/tools/video/route.ts

@@ -976,6 +976,12 @@ async function generateWithModelsLab(
   logger.info(`[${requestId}] Starting ModelsLab video generation, mode: ${mode}`)
 
   const isImg2Video = mode === 'img2video'
+
+  // Validate img2video requires imageUrl
+  if (isImg2Video && !imageUrl) {
+    throw new Error('imageUrl is required for img2video mode')
+  }
+
   const endpoint = isImg2Video
     ? 'https://modelslab.com/api/v6/video/img2video'
     : 'https://modelslab.com/api/v6/video/text2video'