TheLiaoGroup/RXNGraphormer-Reproduction: License and documentation update

This release updates the archived version of the RXNGraphormer-Reproduction repository after adding the MIT License. It corresponds to the final version used for manuscript submission and includes the reproduction experiments, reusability benchmarks, external sequence-generation reusability analysis, figure-generation scripts, evaluation notebooks, and repository documentation. The added license clarifies reuse and redistribution conditions for the reproduction and reusability workflows developed in this repository. The original RXNGraphormer implementation, pretrained checkpoints and third-party components remain subject to their original licensing terms.