Wrap KonnectGatewayControlPlane ControlPlaneSpec into a dedicated field

[mlavacca]

Problem Statement

With the addition of the mirror KonnectGatewayControlPlanes, we had to introduce plenty of CEL rules to validate that no origin-related field is set in case the type is mirror.

Proposed Solution

We need to wrap the original ControlPlaneSpec field into a dedicated originSpec field.

Additional Information

This is a breaking change in the KonnectGatewayControlPlane CRD. we need to evaluate whether to have a conversion webhook in place to avoid disruption is users' configurations.

Acceptance Criteria

• The origin-related fields are wrapped into a dedicated spec field.