Suppress log output when running tests

[utkarsh5026]

Fix: Suppress log output during test runs

Title: Suppress logger output when running under go test

Summary:

• InitDefault() in pkg/logging/logger.go now detects when the process is running under go test via testing.Testing() and redirects the slog handler's writer to io.Discard
• Prevents noisy log output from polluting test results and making failures harder to diagnose
• No change to log behavior in production/non-test execution paths

Changes:

• pkg/logging/logger.go — import testing; conditionally set writer to io.Discard when testing.Testing() returns true