runtimes: enable log export feature

[harshanarayana]

What

This feature adds an ability to export Cluster logs using the k3d binaries.

Why

Tools like kind has been supporting the ability to export logs from the cluster using their native tooling for a while. This ability to export the logs using k3d can be super helpful when doing local development and test experiments. Instead of having to individually collect the logs, this command can be one stop shop for all standard commands to be aggregated.

Implications

This changes the Runtime interface and hence this is a backward incompatible change.

If this is an acceptable change to be included, I will be more than happy to take care of including a few more things to the supported export of logs.

[harshanarayana]

@iwilltry42 PTAL when you can

[harshanarayana]

v1
├── k3d-test-server-0
│   ├── cluster-info.log
│   ├── containerd.log
│   ├── crictl-images.log
│   ├── crictl-ps.log
│   ├── kubectl-get-node.yaml
│   ├── kubectl-version.log
│   ├── log
│   │   ├── containers
│   │   │   ├── coredns-7448499f4d-8dhmx_kube-system_coredns-6dd51f354f8f27ff014ef38849e3ffcfaff1508c7042cd1425f4c7730a6eaaa7.log
│   │   │   ├── helm-install-traefik-crd-gj8kc_kube-system_helm-d769ed944dda3c7e9b130aa01da5094c093dd1e324d2446a4f10445d5f1c8542.log
│   │   │   ├── helm-install-traefik-h964r_kube-system_helm-8d911021b0aae5e12b0273185512a66342308fd73eee32562c213675afa34c13.log
│   │   │   ├── local-path-provisioner-5ff76fc89d-bjf4n_kube-system_local-path-provisioner-0b8f980454508a9f9bd2b9480b94736aa8c5fc0edf7652e9649cfa8b4ad36014.log
│   │   │   ├── metrics-server-86cbb8457f-zwrn7_kube-system_metrics-server-6c05dcf0fa7336f67ac8f2efe2c25f2dc97ee62a0cf3632fe70fbc05264c46a2.log
│   │   │   ├── svclb-traefik-rxrwz_kube-system_lb-port-443-4293306ac37d02a902620275e186abf243a0f84d948224d600dfc5e3626bbf6f.log
│   │   │   ├── svclb-traefik-rxrwz_kube-system_lb-port-80-dbec7113890731d8963a83205812fefbd53fdd907ab3240fa3733f39aaaab574.log
│   │   │   └── traefik-6b84f7cbc-hh6mh_kube-system_traefik-13e5435613b7e5f3c7026a403ae79128fea4c6ceb38a0305e3e9718277ca8a50.log
│   │   ├── k3d-entrypoints_240717122814.log
│   │   └── pods
│   │       ├── kube-system_coredns-7448499f4d-8dhmx_7078afe2-1e8f-443b-a4eb-d2fee1cd6956
│   │       │   └── coredns
│   │       │       └── 0.log
│   │       ├── kube-system_helm-install-traefik-crd-gj8kc_fb93c486-4511-4301-b53f-6794d447eea4
│   │       │   └── helm
│   │       │       └── 0.log
│   │       ├── kube-system_helm-install-traefik-h964r_8562b2fb-7182-462c-b44e-4ee578d8104f
│   │       │   └── helm
│   │       │       └── 0.log
│   │       ├── kube-system_local-path-provisioner-5ff76fc89d-bjf4n_00d2a204-7623-4595-a136-33038c3742a0
│   │       │   └── local-path-provisioner
│   │       │       └── 0.log
│   │       ├── kube-system_metrics-server-86cbb8457f-zwrn7_0be65e2c-bb1f-423f-9b6c-da41927a648a
│   │       │   └── metrics-server
│   │       │       └── 0.log
│   │       ├── kube-system_svclb-traefik-rxrwz_567fab59-c009-4639-83f4-c6e81f75a309
│   │       │   ├── lb-port-443
│   │       │   │   └── 0.log
│   │       │   └── lb-port-80
│   │       │       └── 0.log
│   │       └── kube-system_traefik-6b84f7cbc-hh6mh_9e65392d-4d3a-4290-aa28-7d1e3bab87b4
│   │           └── traefik
│   │               └── 0.log
│   └── ps-aef.log
├── k3d-test-server-0.log
├── k3d-test-serverlb
└── k3d-test-serverlb.log

It will generate a struct like this.