🔴 CRITICAL: Build comprehensive test suite

[GitAddRemote]

Problem

Current test coverage is ~0% with only a smoke test. No unit tests, integration tests, or security tests exist.

Solution

Add Test Dependencies

testImplementation("org.testcontainers:testcontainers:1.19.0")
testImplementation("org.testcontainers:postgresql:1.19.0")
testImplementation("org.testcontainers:kafka:1.19.0")
testImplementation("com.redis.testcontainers:testcontainers-redis:2.0.1")
testImplementation("org.springframework.security:spring-security-test")

Target Coverage

• Overall: 80%+
• Services: 90%+
• Controllers: 80%+

Acceptance Criteria

• All test dependencies added
• Unit tests for all services (JwtService, UserService, LoginRateLimiter)
• Integration tests for all controllers
• Repository tests with Testcontainers
• Security tests for auth flow
• Kafka integration tests
• Test coverage report shows 80%+

Priority

🔴 Critical - Required for production confidence