kctrl to support offline rendering for given AppCr.

**Describe the problem/challenge you have**
Currently, `kctrl` have `dev` subcommand which can be used to deploy an app without having `kapp-ctrl` on the target `Kubernetes` cluster.
That's a very powerful feature. However, as a user of `kctrl` it's not clear as to what the `helm template ` would look like unless it's deployed.

**Describe the solution you'd like**
Once a user has his/her `AppCr.yaml` ready, he/she should be able to leverage `kctrl` to render the app without having a cluster in place.
_Expectation_: `kctrl dev -a --template` should return rendered resources.
* Imgpkg bundle pushed to the registry, creds can be passed through command line args or any other means.
* This should not expect a kubeconfig file or a kubernetes cluster.
* Should not deploy any app on cluster even if kubeconfig is provided.

Example:
Given `AppCr`:
```
apiVersion: kappctrl.k14s.io/v1alpha1
kind: App
...
spec:
deploy:
- kapp:
delete:
rawOptions:
- --apply-ignored=true
rawOptions:
- --diff-changes=true
fetch:
- imgpkgBundle:
image: kind-registry.local:5000/tcxtest/sheikhmo/es-operator:sheikhmo_v1
secretRef:
name: kubelet-pull-secret
serviceAccountName: cluster-admin-sa
syncPeriod: 2m0s
template:
- helmTemplate:
path: es-operator
valuesFrom:
- path: es-operator/values.yaml
- configMapRef:
name: override-es-operator-app-cr-config
- kbld:
paths:
- '-'
- .imgpkg/images.yml
...
```

Expected to see the rendered output, similar to what I see when deploying an app. Like the following:
```
| Target cluster 'https://127.0.0.1:56744/' (nodes: kind-control-plane)
| @@ create serviceaccount/es-operator (v1) namespace: default @@
| 0 + apiVersion: v1
| 1 + kind: ServiceAccount
| 2 + metadata:
| 3 + labels:
| 4 + kapp.k14s.io/app: "1664322049183094000"
| 5 + kapp.k14s.io/association: v1.2d46bb26f0d47b1e8a9796066618739b
| 6 + name: es-operator
| 7 + namespace: default
| 8 +
| @@ create clusterrole/es-operator (rbac.authorization.k8s.io/v1) cluster @@
| 0 + apiVersion: rbac.authorization.k8s.io/v1
| 1 + kind: ClusterRole
| 2 + metadata:
| 3 + labels:
| 4 + kapp.k14s.io/app: "1664322049183094000"
| 5 + kapp.k14s.io/association: v1.cf41f0c7ac
```

That way as a user I would be able to see what resources going to get deployed and what values would look like.

**Anything else you would like to add:**
I believe under the covers that's what `kctrl` does. I.e. pull imgpkg bundle from registry and renders the resources on shell terminal before deploying and app. So, seems like it's possible to achieve this.

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