Run the test suite (requires server running):
# Start server in one terminal
npm start
# Run tests in another terminal
npm testIndividual tests:
npm run test:signatures # Thinking signatures
npm run test:multiturn # Multi-turn with tools
npm run test:streaming # Streaming SSE events
npm run test:interleaved # Interleaved thinking
npm run test:images # Image processing
npm run test:caching # Prompt caching
npm run test:strategies # Account selection strategies
npm run test:cache-control # Cache control field stripping