Overview

This PR implements the full test infrastructure requested across four issues, covering frontend visual regression, SEP-24 flow integration, API coverage enforcement, and webhook reliability under adverse network conditions.

closes #931 — Frontend Snapshot Tests

What was added

• Four React components built from scratch: SendMoneyFlow, TransactionHistory, AgentPanel, CorridorAnalytics
• Vitest snapshot tests for each component covering loading, empty, populated, and interactive states (20 snapshot assertions total)
• Storybook 8 stories wired alongside each component for visual review (Default, Loading, Empty, variant stories)
• frontend/vitest.config.ts configured with jsdom environment, V8 coverage, and snapshot format options
• CI workflow (.github/workflows/frontend-snapshot-tests.yml) that runs snapshots on every PR touching frontend/, builds Storybook, and fails if any snapshot would change without a deliberate update

Snapshot update workflow: run npm run test:snapshot:update inside frontend/, review the diff, commit.

closes #928 — API Service Coverage Reporting

What was added

• api/vitest.config.ts — V8 coverage provider with thresholds: 80% lines, 75% branches, 80% functions, 80% statements
• npm run test:coverage script added to api/package.json
• CI workflow (.github/workflows/api-coverage.yml) that:
  • Runs vitest run --coverage on every PR touching api/
  • Publishes a per-metric pass/fail table to the GitHub Actions step summary
  • Fails the build if any threshold is breached
  • Uploads the full HTML coverage report as a build artifact

closes #927 — SEP-24 Deposit Integration Tests

What was added

• api/src/services/sep24.ts — Sep24Client class: initiateDeposit(), getTransaction(), pollUntilComplete() (with configurable interval/timeout)
• api/src/__tests__/sep24.test.ts — unit tests using mocked axios (happy path, expiry, refund, timeout, header assertions)
• api/src/__tests__/sep24-deposit.integration.test.ts — integration test suite that runs against a real Anchor Platform:
  • Initiate → interactive URL → HTTP reachability check → poll → completed (happy path)
  • Expiry path: poll reaches expired terminal state
  • Refund path: poll reaches refunded with refunds object populated
• tests/docker/sep24-docker-compose.yml — Anchor Platform 3.0.0 + Stellar Quickstart for local/CI reproduction
• api/vitest.integration.config.ts — separate Vitest config with 120s timeout for integration suite
• CI workflow (.github/workflows/sep24-integration-tests.yml) — nightly cron at 02:00 UTC; spins up Docker, obtains SEP-10 JWT, runs integration tests, tears down and publishes summary

Local run:

docker-compose -f tests/docker/sep24-docker-compose.yml up -d
cd api && ANCHOR_PLATFORM_URL=http://localhost:8080 npm run test:integration

closes #930 — Webhook Chaos Tests

What was added

• api/src/services/webhook.ts — deliverWebhook() with exponential backoff (baseDelay × 2^attempt, capped at maxDelayMs), configurable retry count, per-event timeout, and an in-memory DLQ; getDLQ() / clearDLQ() for test inspection
• api/src/__tests__/webhook.test.ts — unit tests: success on first attempt, retry on 503, DLQ after exhausting retries, no retry on 4xx, correct headers, multiple independent DLQ entries
• api/src/__tests__/webhook-chaos.chaos.test.ts — chaos tests using Toxiproxy management API:
  • Baseline (no fault) — delivers on attempt 1
  • +1 s latency (latency toxic) — delivers within timeout
  • Connection reset (reset_peer toxic) — retries and DLQs after max retries
  • 30 s timeout (timeout toxic, 3 s webhook timeout fires first) — DLQs after max retries
  • Exponential backoff — delay array extracted from setTimeout spy grows monotonically
• tests/docker/chaos-docker-compose.yml — Toxiproxy 2.9.0 + Node echo server
• tests/docker/webhook-echo-server.js — minimal HTTP echo server (POST /webhook → 200, GET /health → 200)
• api/vitest.chaos.config.ts — sequential fork pool (Toxiproxy state is shared), 180 s timeout
• CI workflow (.github/workflows/webhook-chaos-tests.yml) — nightly cron at 03:00 UTC; provisions infrastructure, runs chaos suite, publishes fault/behaviour table to step summary

Local run:

docker-compose -f tests/docker/chaos-docker-compose.yml up -d
cd api && TOXIPROXY_URL=http://localhost:8474 WEBHOOK_PROXY_PORT=9090 \
  WEBHOOK_TARGET_URL=http://localhost:3001 npm run test:chaos

Files changed

Closes #931
Closes #928
Closes #927
Closes #930