fix types overrides

[hugoShaka]

This PR fixes the schema_types configuration by:

• not overriding CastFrom with CastTo
• setting go types to the saem times we use to cast from

Required for: gravitational/teleport#61680

Demo

This is my config

schema_types:
  'DiscoveryConfig.spec.aws.Params.JoinMethod':
    type: "github.com/hashicorp/terraform-plugin-framework/types.StringType"
    value_type: "github.com/hashicorp/terraform-plugin-framework/types.String"
    cast_to_type: "string"
    cast_from_type: "github.com/gravitational/teleport/api/types.JoinMethod"

This is the code before this change:

{
	a, ok := tf.Attrs["join_method"]
	if !ok {
		diags.Append(attrReadMissingDiag{"DiscoveryConfig.spec.aws.Params.JoinMethod"})
	} else {
		v, ok := a.(github.com_hashicorp_terraform_plugin_framework_types.String)
		if !ok {
			diags.Append(attrReadConversionFailureDiag{"DiscoveryConfig.spec.aws.Params.JoinMethod", "github.com/hashicorp/terraform-plugin-framework/types.String"})
		} else {
			// this is the wrong type, should match the type from `cast_from_type` but is trying to find the type in the proto package (doesn't make sense as we are in an override)
			var t github.com_gravitational_teleport_api_gen_proto_go_teleport_discoveryconfig_v1.JoinMethod
			if !v.Null && !v.Unknown {
				// this is using the `cast_to` instead of the `cast_from`
				t = string(v.Value)
			}
			obj.JoinMethod = t
		}
	}
}

This is the code after this change:

{
	a, ok := tf.Attrs["join_method"]
	if !ok {
		diags.Append(attrReadMissingDiag{"DiscoveryConfig.spec.aws.Params.JoinMethod"})
	} else {
		v, ok := a.(github.com_hashicorp_terraform_plugin_framework_types.String)
		if !ok {
			diags.Append(attrReadConversionFailureDiag{"DiscoveryConfig.spec.aws.Params.JoinMethod", "github.com/hashicorp/terraform-plugin-framework/types.String"})
		} else {
			var t github.com_gravitational_teleport_api_types.JoinMethod
			if !v.Null && !v.Unknown {
				t = github.com_gravitational_teleport_api_types.JoinMethod(v.Value)
			}
			obj.JoinMethod = t
		}
	}
}

[hugoShaka]

I'll cut the release once the PR is merged. I'm just lazy and don't want to do a second PR just to bump the version

[r0mant]

Bot.