fix(frontend): fix infinite loop in PublishAgentModal and simplify useThumbnailImages

- Changed updateState to setCurrentState in usePublishAgentModal to prevent circular dependency
- Simplified useThumbnailImages by using JSON.stringify for stable dependency tracking instead of manual refs
- Removed duplicate helpers.ts file from MainAgentPage
- All changes preserve functionality while reducing code complexity

🤖 Generated with [Claude Code](https://claude.ai/code)

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

autogpt_platform/frontend/src/app/(platform)/marketplace/components/MainAgentPage/helpers.ts

@@ -1,54 +0,0 @@
-/**
- * Calculate the latest marketplace version from agent graph versions
- */
-export function getLatestMarketplaceVersion(
-  agentGraphVersions?: string[],
-): number | undefined {
-  if (!agentGraphVersions?.length) return undefined;
-
-  return Math.max(...agentGraphVersions.map((v: string) => parseInt(v, 10)));
-}
-
-/**
- * Check if the current user is the creator of the agent
- */
-export function isUserCreator(
-  creator: string,
-  currentUser: { email?: string } | null,
-): boolean {
-  if (!currentUser?.email) return false;
-
-  const userHandle = currentUser.email.split("@")[0]?.toLowerCase() || "";
-  return creator.toLowerCase().includes(userHandle);
-}
-
-/**
- * Calculate update status for an agent
- */
-export function calculateUpdateStatus({
-  latestMarketplaceVersion,
-  currentVersion,
-  isUserCreator,
-  isAgentAddedToLibrary,
-}: {
-  latestMarketplaceVersion?: number;
-  currentVersion: number;
-  isUserCreator: boolean;
-  isAgentAddedToLibrary: boolean;
-}) {
-  if (!latestMarketplaceVersion) {
-    return { hasUpdate: false, hasUnpublishedChanges: false };
-  }
-
-  const hasUnpublishedChanges =
-    isUserCreator &&
-    isAgentAddedToLibrary &&
-    currentVersion > latestMarketplaceVersion;
-
-  const hasUpdate =
-    isAgentAddedToLibrary &&
-    !isUserCreator &&
-    latestMarketplaceVersion > currentVersion;
-
-  return { hasUpdate, hasUnpublishedChanges };
-}

autogpt_platform/frontend/src/components/contextual/PublishAgentModal/components/AgentInfoStep/components/useThumbnailImages.ts

@@ -23,38 +23,18 @@ export function useThumbnailImages({
 
   const [isGenerating, setIsGenerating] = useState(false);
   const thumbnailsContainerRef = useRef<HTMLDivElement | null>(null);
-  const prevInitialImagesRef = useRef<string[]>([]);
-  const prevInitialSelectedRef = useRef<string | null>(null);
   const { toast } = useToast();
 
-  // Update images when initialImages prop changes
+  // Memoize the stringified version to detect actual changes
+  const initialImagesKey = JSON.stringify(initialImages);
+
+  // Update images when initialImages prop changes (by value, not reference)
   useEffect(() => {
-    const hasInitialImagesChanged =
-      initialImages.length !== prevInitialImagesRef.current.length ||
-      initialImages.some(
-        (img, index) => img !== prevInitialImagesRef.current[index],
-      );
-
-    const hasInitialSelectedChanged =
-      initialSelectedImage !== prevInitialSelectedRef.current;
-
-    if (
-      initialImages.length > 0 &&
-      (hasInitialImagesChanged || hasInitialSelectedChanged)
-    ) {
+    if (initialImages.length > 0) {
       setImages(initialImages);
-      // Set selectedImage if initialSelectedImage is provided
-      if (initialSelectedImage) {
-        setSelectedImage(initialSelectedImage);
-      } else {
-        setSelectedImage(initialImages[0]);
-      }
-
-      // Update refs
-      prevInitialImagesRef.current = initialImages;
-      prevInitialSelectedRef.current = initialSelectedImage;
+      setSelectedImage(initialSelectedImage || initialImages[0]);
     }
-  }, [initialImages, initialSelectedImage]);
+  }, [initialImagesKey, initialSelectedImage]); // Use stringified key instead of array reference
 
   // Notify parent when images change
   useEffect(() => {

autogpt_platform/frontend/src/components/contextual/PublishAgentModal/usePublishAgentModal.ts

@@ -151,10 +151,10 @@ export function usePublishAgentModal({
 
     // Update the state with the submission data if this is an update
     if (publishedSubmissionData) {
-      updateState({
-        ...currentState,
+      setCurrentState((prevState) => ({
+        ...prevState,
         submissionData: publishedSubmissionData,
-      });
+      }));
     }
   }, [
     targetState,