Rename isBskyPds to isBlackskyPds and fix bundleIdentifier default
- Rename isBskyPds to isBlackskyPds in analytics metadata, utils,
and GrowthBook attributes to reflect Blacksky PDS branding
- Change bundleIdentifier fallback from hardcoded 'dev' to use
EXPO_PUBLIC_ENV so builds correctly report 'staging' or 'production'