Link training dataset in introduction

Summarize model highlights and compact evaluation table

Update training example to load the released model

docs: add GitHub repository badge

Update README.md

Link released inference, training code and OpenJevData

Clarify accuracy and Brier definitions

Simplify model summary and remove mathematical notation

Add five-model comparisons on MMDM and JevBench Public

Document OpenJev architecture, SFT and REINFORCE-Analysis, and evaluation results

Upload OpenJev-4B model weights and loading configuration

initial commit