Converting RAW to HEIC inside Apple Photos: App Intents, HDR gain maps, and never losing a metadata field

I built an iOS/iPadOS/macOS app called RawToHEIC. The pitch is one sentence: you select RAW photos in the Photos app, tap Share, pick "Convert RAW to HEIC," and a few seconds later your library has HEICs that are up to 10× smaller — with every edit, album, favorite, and GPS coordinate intact. That s