add-a-bat

Add a new bat listing to BatDigest by creating a new entry in `data/bats.yaml`, researching missing specs (JustBats/manufacturer), and generating affiliate links; then optionally proceed to add ratings and bat images (R2 upload + `data/images.yaml`). Use when asked to "add a bat", "create a bat listing", "add to bats.yaml", "add ratings", or "attach bat images".