Feat: Add the backend plugin framework

[barnettZQG]

Description of your changes

This PR has three goals:

1. Proxy the Kubernetes API and external services that discover the endpoint by Kubernetes service by plugin config.
2. The allowed route and the permission can be customized for all proxy APIs. The authorization is the same as that of OpenAPI.
3. Generate the cluster role for every plugin that type is kube-api to limit the permission.

Plugin Definition

{
  "type": "page-app",
  "name": "Node Dashboard",
  "id": "node-dashboard",
  ...
  "backend": true,
  "proxy": true,
  "backendType": "kube-api",
  "kubePermissions": [
    {
      "apiGroups": [
        ""
      ],
      "resources": [
        "nodes",
        "nodes/status"
      ],
      "verbs": [
        "get",
        "list"
      ]
    },
    {
      "apiGroups": [
        "",
        "events.k8s.io"
      ],
      "resources": [
        "events"
      ],
      "verbs": [
        "get",
        "list"
      ]
    }
  ],
  "routes": [
    {
      "path": "/api/v1/nodes",
      "permission": {
        "resource": "node",
        "action": "list"
      }
    },
    {
      "path": "/api/v1/events",
      "permission": {
        "resource": "event",
        "action": "list"
      }
    },
    {
      "path": "/api/v1/nodes/:nodeName",
      "method": "Put",
      "permission": {
        "resource": "node",
        "action": "update"
      },
      "resourceMap": {
        "node": "nodeName"
      }
    }
  ],
  "includes": [
    {
      "workspace": {
        "name": "platform-setting"
      },
      "type": "Workspace",
      "label": "Node Manage",
      "name": "node-manage",
      "to": "/plugins/%PLUGIN_ID%",
      "permission": {
        "resource": "node",
        "action": "list"
      },
      "relatedRoute": [
        "/plugins/%PLUGIN_ID%"
      ],
      "icon": "",
      "catalog": "Resources"
    }
  ]
}

• backendType: The options include kube-api, kube-service, and static-server
• kubePermissions: This field defines the permission policy of the cluster role. Only available for the kube-api type.
• routes: This field defines the allowed route. The empty route means allowing all APIs. Every route could define the needed permission.

For this example plugin config, follow APIs are available:

• GET: /proxy/plugins/node-dashboard/api/v1/nodes
• PUT: /proxy/plugins/node-dashboard/api/v1/nodes/node-name
• GET: /proxy/plugins/node-dashboard/api/v1/events

I have:

• Read and followed KubeVela's contribution process.
• Related Docs updated properly. In a new feature or configuration option, an update to the documentation is necessary.
• Run yarn lint to ensure the frontend changes are ready for review.
• Run make reviewableto ensure the server changes are ready for review.
• Added backport release-x.y labels to auto-backport this PR if necessary.

Special notes for your reviewer

[codecov]

Codecov Report

Patch coverage: 57.60% and no project coverage change.

Comparison is base (bceaad7) 61.08% compared to head (47a62bf) 61.09%.

Additional details and impacted files

@@           Coverage Diff            @@
##             main     #740    +/-   ##
========================================
  Coverage   61.08%   61.09%            
========================================
  Files          99      106     +7     
  Lines       18081    18543   +462     
========================================
+ Hits        11045    11328   +283     
- Misses       5693     5826   +133     
- Partials     1343     1389    +46     

Flag	Coverage Δ
apiserver-unittests	33.14% <45.32%> (+0.58%)	⬆️
server-e2e-tests	49.91% <45.60%> (-0.09%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
pkg/plugin/loader/loader.go	45.39% <0.00%> (-6.10%)	⬇️
pkg/plugin/proxy/static_server_proxy.go	0.00% <0.00%> (ø)
pkg/plugin/types/plugin.go	40.00% <ø> (+10.00%)	⬆️
pkg/server/interfaces/api/dto/v1/types.go	73.33% <ø> (ø)
pkg/server/utils/bcode/bcode.go	55.10% <ø> (ø)
pkg/server/server.go	56.16% <39.28%> (-2.51%)	⬇️
pkg/plugin/proxy/kube_service_proxy.go	42.85% <42.85%> (ø)
pkg/plugin/proxy/proxy.go	50.00% <50.00%> (ø)
pkg/server/domain/model/plugin.go	50.00% <50.00%> (ø)
pkg/server/interfaces/api/authentication.go	48.03% <52.63%> (+2.18%)	⬆️
... and 6 more

... and 5 files with indirect coverage changes

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[wonderflow]

rbacPolicies

[wonderflow]

great job