feat: BrandMessageRotator — rotating privacy copy across screens (batch v0.2.9)
- Add CloserBrandCopy with 6 approved privacy messages
- Add BrandMessageRotator composable: animated fade rotation every 4.5s, reduced-motion support
- Integrate rotator into: OnboardingScreen (CTA + auth check), LoginScreen, LoadingState, AnswerRevealScreen (waiting card), WaitingForPartnerScreen, DesireSync/HowWell/ThisOrThat waiting screens
- Add CloserBrandCopyTest for uniqueness and length validation
- Update visual-identity.md with approved rotation and security-claim publishing rules
9a0b2b6a3d