Continuous Integration with AWS CDK ECS and Prisma

Question

I'm setting up CI/CD while collaborating with CDK. My stack appears to be:

AppStack L2: Two ECS Services

L1: RDS Database Storage Stack

L0: Networks: SharedInfrastructure

It's not really obvious how to set up CI. For instance, I'm not clear whether migrations should take place in AppStack or StorageStack because I'm using Prisma. How should I carry out these migrations, furthermore? Is it sensible to configure a Serverless function to be called whenever a change is discovered? However, each time the Prisma schema is revised, this function must also be updated. What occurs if there could be a data loss?

I may not be seeing everything, but I'm hoping someone can shed some light. Thanks!