Metadata correction for 2024.findings-emnlp.306

### JSON data block

```json
{
"anthology_id": "2024.findings-emnlp.306",
"authors": [
{
"first": "Felipe S. F.",
"last": "Paula",
"id": "felipe-paula/unverified"
},
{
"first": "Cassiana R. L.",
"last": "Michelin",
"id": "cassiana-roberta-lizzoni-michelin/unverified"
},
{
"first": "Viviane P.",
"last": "Moreira",
"id": "viviane-moreira"
}
],
"authors_old": "Felipe Paula | Cassiana Roberta Lizzoni Michelin | Viviane Moreira",
"authors_new": "Felipe S. F. Paula | Cassiana R. L. Michelin | Viviane P. Moreira"
}
```

Start by searching the repository for anthology_id "2024.findings-emnlp.306" to find the matching metadata entry. Compare its authors field with the payload’s authors_old value and replace it with authors_new. Verify only that record is changed and keep formatting consistent with nearby metadata entries; no test files are mentioned in the issue.

索引モデルが issue の本文から書いたものです。