skaffold init/dev to support deployment-less configs

### Expected behavior

[As agreed with Tejal, I'm going to dump my thoughts here].
As a developer, I would like to use skaffold as a iteration process for early building my dockerized application.
At early stages, I wouldn't want to run it on kubernetes, or even minikube, I would probably use a quick and simple
docker-compose kind of functionality. However, skaffold has way better functionalities, it allows me to change the code
while its watch function will automatically re-issue a docker build only if necessary, fotentimes will just push diff of my code into the docker container.

THIS IS GOLD!

However, this gold has a price. I need to provide to the system a Dockerfile (reasonable) and k8s manifests (unreasonable).
The way I see it, k8s manifests will come after I've tried my software. Now, I believe this product should choose TWO ways:

1. Drop this need and allow INIT/DEV without k8s.
```
$ skaffold init --skip-manifests-check
```

2. Keep this need but then give me a sample, naive single-pod configuration and create it for myself.

```
$ skaffold init --create-silly-manifest-for-me
```
### Actual behavior

```
$ skaffold init
WARN[0000] Skipping Jib: no JVM: [java -version] failed: exit status 1 subtask=-1 task=DevLoop
one or more valid Kubernetes manifests are required to run skaffold
```

### Information

- Skaffold version: v1.35.1
- Operating system: Mac OSX
- Installed via: $ which skaffold /Users/ricc/google-cloud-sdk/bin/skaffold
- Contents of skaffold.yaml: