feat: Better Helm design

*Description*:
The official Helm chart for the Gateway component should be more robust and comprehensive. Currently, it seems to lack resources for managing deployments of GatewayClass, Gateway, and other child objects associated with CRDs. Values file should be more configurable.

Extract all Kubernetes resource definitions related to the Gateway component from the source code (like this example with statsd: https://github.com/envoyproxy/gateway/blob/301eeddfa4c2f7e4e612874a9c5b13a976156c3e/internal/infrastructure/kubernetes/ratelimit/resource.go#L205 ) and consolidate them into a single location. This improves maintainability over Helm chart.

Ideally, the Helm chart should provide a single point of control to manage the creation and configuration of GatewayClass, Gateway, and other related CRD objects.