feat: add per-host path prefix support to ingress template

What

Enhance ingress routing rules by adding support for per-host path prefix support. It remains backwards compatible so the existing ingress.hosts entries will continue to work.

For example:

ingress:
  hosts:
    - foo.com # will configure foo.com with prefix match for /
    - host: "bar.com"
      pathPrefix: "/foo"
      pathType: "Exact"

Why

The current path match isn't very configurable: you can't match on specific paths or different path types (prefix, exact) so this change makes it more configurable.

Related to (and getting ahead of) https://gitlab.com/gitlab-com/gl-infra/platform/runway/team/-/issues/636#note_2740511097.