s3 image file validation

frontend/src/config/imageLimits.ts

@@ -0,0 +1,11 @@
+/**
+ * Image upload limits configuration
+ * Keep in sync with backend/config/imageLimits.js
+ */
+export const IMAGE_LIMITS = {
+  items: 10,
+  forum: 10,
+  conditionChecks: 10,
+  profile: 1,
+  messages: 1,
+} as const;