Implement WafPolicy controller & generate the correct NGINX configuration

[ciarams87]

As a user of NGF
I want my WafPolicy configuration applied to NGINX for the Gateway or Route scope
So that I can enable WAF protection on my traffic

Acceptance

• Validate the WafPolicies
  • Parameters contained in the policy
  • The targetRef detailed in the policy
• Add the WafPolicies to the graph
• Ensure I can create WafPolicy targeting Gateway and HTTPRoute and GRPCRoute and that inheritance is correctly applied
• Apply the app_protect directives to the NGINX config (TBD - for inheritance can I apply the config at server level for Gateway and location for HTTPRoute and let NGINX precedence handle the inheritance?)