- Renamed Decoder (and decoder.py) to GptDecoder (gpt_decoder.py) for clarity in GPT1
- Implemented support for cache and use_cache parameters in GptDecoder.forward (API unification)
- Adapted all usages in GPT model to use new decoder structure and handle tuple output
- Refactored core tests (test_gpt.py, test_gpt_decoder.py, test_basic.py) to correctly expect tuple or logits and ensure shape/device checks work as before
- Improved clarity and future extensibility for autoregressive generation and benchmarking
- No changes to architectural details or training loop; pure API and test modernization