Adding retry logic with exponential backoff for API calls

[JoeColeman95]

Changes

• Automatic retry logic added API calls with exponential backoff and jitter
• Retries transient failures such as 5xx server errors, 429 rate limits, and network errors
• Fast-fails on non-retryable errors (4xx errors (except 429))
• Backoff capped at 60 seconds per retry
• Applies to both build creation and status polling
• Build creation POST will automatically retry
• Build status polling GET requests will retry when wait: true
• Default retries for POST (5 retries, base delay of 2s which increases per try)
• Added 6 new test cases for retry scenarios (tests 26-32)
• Updated all existing tests to work with new retry wrapper
• All 32 tests passing
• Set delay to 0s on retries so it's not painful to wait
• Manually tested in GHA workflow
• Updated README.md with retry behavior
• Added .gitignore for test-generated files
• Bumped to v2.4.1 (release will be cut upon merge)

[lizrabuya]

This is great! 🚀