feat(frontend): harden banks API and instrument status telemetry

Author: Anthony-19

Dechat/dex_with_fiat_frontend/src/components/OfflineStatusBanner.test.tsx

@@ -1,5 +1,5 @@
 import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
-import { renderHook, act } from '@testing-library/react';
+import { act } from '@testing-library/react';
 import { render, screen, waitFor } from '@testing-library/react';
 import OfflineStatusBanner from './OfflineStatusBanner';
 import * as offlineMessageQueue from '@/lib/offlineMessageQueue';

Dechat/dex_with_fiat_frontend/src/components/OfflineStatusBanner.tsx

@@ -1,11 +1,11 @@
 'use client';
 
-import { useEffect, useState, useCallback, useRef } from 'react';
+import { useEffect, useState, useRef } from 'react';
 import { AlertTriangle, WifiOff } from 'lucide-react';
 import { useOnlineStatus } from '@/hooks/useOnlineStatus';
 import { useToast } from '@/hooks/useToast';
 import { offlineStatusToastSchema } from '@/lib/offlineStatusSchema';
-import { subscribeToQueuedMessageCount, setQueuedMessageCount, getQueuedMessageCount } from '@/lib/offlineMessageQueue';
+import { subscribeToQueuedMessageCount } from '@/lib/offlineMessageQueue';
 
 /**
  * Offline Status Banner Component
@@ -18,7 +18,6 @@ export default function OfflineStatusBanner() {
   const { addToast } = useToast();
   const [showBanner, setShowBanner] = useState(false);
   const [isLoading, setIsLoading] = useState(true);
-  const [pendingCount, setPendingCount] = useState(0);
   const [optimisticPendingCount, setOptimisticPendingCount] = useState(0);
   const [isReconnecting, setIsReconnecting] = useState(false);
   const previousOnlineState = useRef<boolean>(true);
@@ -33,23 +32,10 @@ export default function OfflineStatusBanner() {
 
   useEffect(() => {
     return subscribeToQueuedMessageCount((count) => {
-      setPendingCount(count);
       setOptimisticPendingCount(count);
     });
   }, []);
 
-  // Optimistic update: increment pending count immediately when message is queued
-  const optimisticallyIncrementPending = useCallback(() => {
-    setOptimisticPendingCount((prev: number) => prev + 1);
-    setQueuedMessageCount(getQueuedMessageCount() + 1);
-  }, []);
-
-  // Optimistic update: decrement pending count immediately when message is sent
-  const optimisticallyDecrementPending = useCallback(() => {
-    setOptimisticPendingCount((prev: number) => Math.max(0, prev - 1));
-    setQueuedMessageCount(Math.max(0, getQueuedMessageCount() - 1));
-  }, []);
-
   useEffect(() => {
     // Optimistic UI: Show banner immediately when going offline
     if (!isOnline && previousOnlineState.current) {

Dechat/dex_with_fiat_frontend/src/hooks/useStatusTelemetry.test.tsx

@@ -15,7 +15,8 @@ class MockEventSource {
   onerror: (() => void) | null = null;
   close = vi.fn();
 
-  constructor(_url: string) {
+  constructor(url: string) {
+    void url;
     MockEventSource.latest = this;
   }
 }

Dechat/dex_with_fiat_frontend/src/lib/aiAssistant.test.ts

@@ -240,8 +240,7 @@ describe('AIAssistant abort signal support', () => {
 
     expect(toastAddMock).toHaveBeenCalled();
     consoleErrorSpy.mockRestore();
-
-
+  });
 });
 
 /**

Dechat/dex_with_fiat_frontend/src/lib/apiSchemas.test.ts

@@ -46,7 +46,6 @@ describe('apiSchemas - Request Retry with Exponential Backoff', () => {
         .mockRejectedValueOnce(new TypeError('Failed to fetch'))
         .mockResolvedValue('success');
 
-      const startTime = Date.now();
       const promise = withRetry(fn, { initialDelayMs: 100, maxRetries: 2 });
 
       // Advance timers for first retry

Dechat/dex_with_fiat_frontend/src/lib/apiSchemas.ts

@@ -53,6 +53,11 @@ export interface RetryConfig {
   retryableErrors?: (error: unknown) => boolean;
 }
 
+interface HttpError extends Error {
+  status?: number;
+  response?: Response;
+}
+
 /**
  * Default retry configuration
  */
@@ -140,8 +145,12 @@ export async function withRetry<T>(
       // Check if error is retryable
       const isRetryableError = mergedConfig.retryableErrors(error);
       const isRetryableStatus =
-        error instanceof Response &&
-        mergedConfig.retryableStatusCodes.includes(error.status);
+        error instanceof Response
+          ? mergedConfig.retryableStatusCodes.includes(error.status)
+          : error instanceof Error &&
+              mergedConfig.retryableStatusCodes.includes(
+                (error as HttpError).status ?? 0,
+              );
 
       if (!isRetryableError && !isRetryableStatus) {
         throw error; // Non-retryable error, throw immediately
@@ -175,9 +184,10 @@ export async function fetchWithRetry(
 
     if (!response.ok) {
       // Throw error to trigger retry for non-OK responses
-      const error = new Error(`HTTP ${response.status}: ${response.statusText}`);
-      (error as any).status = response.status;
-      (error as any).response = response;
+      const error: HttpError = Object.assign(
+        new Error(`HTTP ${response.status}: ${response.statusText}`),
+        { status: response.status, response },
+      );
       throw error;
     }