Add subcription level filtering

frontend/src/api/client/apiClient.ts

@@ -18,6 +18,27 @@ export interface ApiError {
   details?: any;
 }
 
+export interface SubscriptionError {
+  error: string;
+  message: string;
+  code: string;
+  details: {
+    required_feature: string;
+    required_level: string;
+    current_plan: string;
+    upgrade_url: string;
+  };
+}
+
+// Subscription error event emitter
+class SubscriptionErrorEmitter extends EventTarget {
+  emitSubscriptionError(error: SubscriptionError) {
+    this.dispatchEvent(new CustomEvent('subscriptionError', { detail: error }));
+  }
+}
+
+export const subscriptionErrorEmitter = new SubscriptionErrorEmitter();
+
 class ApiClient {
   private client: AxiosInstance;
   private baseURL: string;
@@ -146,6 +167,13 @@ class ApiClient {
     if (error.response) {
       // Server responded with error status
       const { status, data } = error.response;
+
+      // Check for subscription errors
+      if (status === 403 && (data as any)?.code === 'SUBSCRIPTION_UPGRADE_REQUIRED') {
+        const subscriptionError = data as SubscriptionError;
+        subscriptionErrorEmitter.emitSubscriptionError(subscriptionError);
+      }
+
       return {
         message: (data as any)?.detail || (data as any)?.message || `Request failed with status ${status}`,
         status,