feat(chart): Merge http and grpc traffic with Gateway API

[Filip7656]

The Helm chart currently treats HTTP and gRPC using separate domains which creates a lot of DNS entries for chainloop installation. With the Gateway API, it is possible to route both HTTP and gRPC traffic through a single HTTPRoute using content-type–based matching.
This issue is connected to #2641 and has to be done after.

Proposed enhancement

Add Helm chart support for defining combined HTTP and gRPC routing under a single HTTPRoute, including:
- Shared hostnames and listeners
- Path-based routing for HTTP traffic
- Header-based routing for gRPC traffic (e.g. content-type: application/grpc)

High level example of how this would work using httpRoute:

apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: app
spec:
  hostnames:
    - cp.chainloop.com
  rules:
    - matches:
        - headers:
            - name: content-type
              value: application/grpc
      backendRefs:
        - name: cp-grpc
          port: 80
    - matches:
        - path:
            type: PathPrefix
            value: /
      backendRefs:
        - name: cp-http
          port: 80

The same can be done for Artifact CAS service.