Release aTrain_core v1.2.1

We are happy to release aTrain_core v.1.2.1 forming the basis of our improvements and additional features in aTrain v.1.2.1.

• Add functionality for checking if models have been changed
• Lazy-load torch and pyannote for faster app startup
• Enabling initial prompts thanks to the contribution of @Bytestorm5
• Add float32 to possible inputs