proxy: Expose cachedSelectorREEntry type, regex map retrieval
proxy: Expose cachedSelectorREEntry type, regex map retrieval

This type will be useful for serializing cache entries for communication
between agent and external components

Signed-off-by: Maciej Kwiek <33c1fdf481c8e628d4c6db7ea8dc77f49f2fa5d7@isovalent.com>

tklauser/cilium,michi-covalent/cilium,michi-covalent/cilium,michi-covalent/cilium,cilium/cilium,cilium/cilium,tklauser/cilium,cilium/cilium,cilium/cilium,tklauser/cilium,tklauser/cilium,michi-covalent/cilium,tklauser/cilium,cilium/cilium,michi-covalent/cilium