enhancement(controlplane): versioned migrations support

[migmartri]

Adds support for versioned migrations

The reason for using versioned migrations is because it enables advanced DB changes which will be required during #201. For example db table rename oci_repositories => cas_backends or non-null DB column with values set for current entries, i.e provider = OCI.

It makes it look closer to how rails migrations works although it still relies on the declarative schema from ent.

It adds an initial migration with the current DB schema

• app/controlplane/internal/data/ent/migrate/migrations/20230706165452_init-schema.sql

Note:

We'll need to add support for automatic migrations in our Helm Chart via an init container. There is a brand new container image that will be built during release that contains the migrations.

Refs #221