Repair GenomeOcean-500M-v1.2 weights: replace mistakenly duplicated base-model blob with the correct continued-training checkpoint; preserve v1.2 metadata for expanded GTDB/phage/RNA-virus training

Update README.md

Upload GenomeOcean-500M-v1.2: expanded dataset with GTDB r226, INPHARED phage, and Zenodo RNA virus database; [CLS] domain tags and [SEP] genome boundaries

initial commit