Release 1.51.0

**site-templates:** reuse onboarding buttons and adopt the Figma card spec ([1075386](https://github.com/TheFlowOps-Eng/fo-class-experience/commit/1075386c992e1d6d5128b259cc13adc6c8dd4af7))

**site-templates:** keep Preview a real link and drop the kebab ([8ac95b0](https://github.com/TheFlowOps-Eng/fo-class-experience/commit/8ac95b06df5543f35035099c665bbeb22c6c0e1b))