Photo re-enable: frontend HEIC transcode + EXIF strip (Unit-A)

When photo upload is re-enabled (CR24 removed it; personaEventPhotos table retained), use the fleet Unit-A pattern per bs-mr4rxrzvd5e: FRONTEND canvas/heic2any re-encode HEIC/HEIF/PNG/WEBP→JPEG + downscale below cap BEFORE upload — this fixes iPhone-HEIC + >5MB AND drops EXIF/GPS as a free side effect (privacy-critical: ayudarg photographs vulnerable persons, GPS leak = safety risk). Fallback = shared per-format strip util (coder-apiimages, vendored) for any non-transcoded/doc bytes. api-images stays a thin byte store.