Add full client side zod validation when creating an Entry - including it's Values

[Nils-Kolvenbach]

Currently the Client only validates against createEntrySchema when creating a new Entry. Here, values is a pretty generic array of unions that can be any possible Value.

Inside Core we are going a step further by validating each given Value by it's definition. This is done by finding the definition by ID and then calling the getValueContentSchemaFromDefinition() method of @elek-io/shared with it. This method generates the schema based on given definition which is then used to validate the Value with.

Because we are not doing the same thing on the Client, we only display a generic notification for the user if the schema validation fails inside Core. Ideally we can do the same we do in Core also in Client, to highlight the fields on errors and display the correct message next to it.