add MultiClusterService API

[XiShanYongYe-Chang]

What type of PR is this?

/kind api-change

What this PR does / why we need it:

add MultiClusterService API

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE(part of the feature)

[RainbowMango]

Please look at the alternative:

// MultiClusterService is a named abstraction of multi-cluster software service.
// The name field of MultiClusterService is the same as that of Service name.
// Services with the same name in different clusters are regarded as the same
// service and are associated with the same MultiClusterService.
// MultiClusterService can control the exposure of services to outside multiple
// clusters, and also enable service discovery between clusters.
type MultiClusterService struct {
	metav1.TypeMeta   `json:",inline"`
	metav1.ObjectMeta `json:"metadata,omitempty"`

	// Spec is the desired state of the MultiClusterService.
	// +optional
	Spec MultiClusterServiceSpec `json:"spec,omitempty"`

	// Status is the current state of the MultiClusterService.
	// +optional
	Status corev1.ServiceStatus `json:"status,omitempty"`
}

// MultiClusterServiceSpec is the desired state of the MultiClusterService.
type MultiClusterServiceSpec struct {
	// ExposureMethods specifies how to expose the service referencing by this
	// MultiClusterService.
	//
	// +required
	ExposureMethods []ExposureMethod `json:"exposureMethods"`

	// ExposurePort specifies which port of the referencing service should be
	// exposed.
	// Only required when a service have more than one port.
	// +optional
	ExposurePort ExposurePort `json:"exposurePort,omitempty"`

	// ExposureRange specifies the ranges where the referencing service should
	// be exposed.
	// Only valid and optional in case of ExposureMethods contains CrossCluster.
	// If not set and ExposureMethods contains CrossCluster, all clusters will
	// be selected, that means the referencing serviced will be exposed across
	// all registered clusters.
	// +optional
	ExposureRange ExposureRange `json:"exposureRange,omitempty"`
}

// ExposureMethod describes how to expose the service.
type ExposureMethod string

const (
	// ExposureMethodCrossCluster means a service will be accessible across clusters.
	ExposureMethodCrossCluster ExposureMethod = "CrossCluster"

	// ExposureMethodLoadBalancer means a service will be exposed via an external
	// load balancer.
	ExposureMethodLoadBalancer ExposureMethod = "LoadBalancer"
)

// ExposurePort describes which port will be exposed.
type ExposurePort struct {
	// Name is the name of the port that needs to be exposed within the service.
	// The port name must be the same as that defined in the service.
	// +optional
	Name string `json:"name,omitempty"`

	// Port specifies the exposed service port.
	// +optional
	Port int32 `json:"port,omitempty"`
}

// ExposureRange describes a list of clusters where the service is exposed.
// Now supports selecting cluster by name, leave the room for extend more methods
// such as using label selector.
type ExposureRange struct {
	// ClusterNames is the list of clusters to be selected.
	// +optional
	ClusterNames []string `json:"clusterNames,omitempty"`
}

[GitHubxsy]

#3644 (review)
Exposure prefix is ​​redundant

[RainbowMango]

Echo from https://github.com/karmada-io/karmada/actions/runs/5375174785/jobs/9751322967?pr=3644

13m 38s
Run ct install --debug --helm-extra-args "--timeout 800s"
Installing charts...
>>> helm version --short
>>> git rev-parse --is-inside-work-tree
>>> git merge-base origin/master HEAD
>>> git diff --find-renames --name-only 276428e0eeae90272d473d269[1](https://github.com/karmada-io/karmada/actions/runs/5375174785/jobs/9751322967?pr=3644#step:10:1)c10b1bf1f10d88 -- charts

------------------------------------------------------------------------------------------------------------------------
 Charts to be processed:
------------------------------------------------------------------------------------------------------------------------
 karmada => (version: "0.0.0", path: "charts/karmada")
------------------------------------------------------------------------------------------------------------------------

>>> helm dependency build charts/karmada
Hang tight while we grab the latest from your chart repositories...
...Successfully got an update from the "bitnami" chart repository
Update Complete. ⎈Happy Helming!⎈
Saving 1 charts
Downloading common from repo https://charts.bitnami.com/bitnami
Deleting outdated charts
Installing chart 'karmada => (version: "0.0.0", path: "charts/karmada")'...
Creating namespace 'karmada-xhfmy98ebo'...
>>> kubectl create namespace karmada-xhfmy98ebo
namespace/karmada-xhfmy98ebo created
>>> helm install karmada-xhfmy98ebo charts/karmada --namespace karmada-xhfmy98ebo --wait --timeout 800s
Error: INSTALLATION FAILED: failed pre-install: warning: Hook pre-install karmada/templates/pre-install-job.yaml failed: ConfigMap "karmada-xhfmy98ebo-config" is invalid: []: Too long: must have at most 1048576 bytes
========================================================================================================================
........................................................................................................................
==> Events of namespace karmada-xhfmy98ebo
........................................................................................................................
>>> kubectl get events --output wide --namespace karmada-xhfmy98ebo
No resources found in karmada-xhfmy98ebo namespace.
........................................................................................................................
<== Events of namespace karmada-xhfmy98ebo
........................................................................................................................
>>> kubectl get pods --no-headers --namespace karmada-xhfmy98ebo --selector  --output jsonpath={.items[*].metadata.name}
========================================================================================================================
Deleting release 'karmada-xhfmy98ebo'...
>>> helm uninstall karmada-xhfmy98ebo --namespace karmada-xhfmy98ebo --timeout 800s
Error: uninstallation completed with 1 error(s): timed out waiting for the condition
Error deleting Helm release: Error waiting for process: exit status 1
Deleting namespace 'karmada-xhfmy98ebo'...
>>> kubectl delete namespace karmada-xhfmy98ebo --timeout [18](https://github.com/karmada-io/karmada/actions/runs/5375174785/jobs/9751322967?pr=3644#step:10:19)0s
namespace "karmada-xhfmy98ebo" deleted
>>> kubectl get namespace karmada-xhfmy98ebo
Error: Error installing charts: Error processing charts
Namespace 'karmada-xhfmy98ebo' terminated.
------------------------------------------------------------------------------------------------------------------------
 ✖︎ karmada => (version: "0.0.0", path: "charts/karmada") > Error waiting for process: exit status 1
------------------------------------------------------------------------------------------------------------------------
Error installing charts: Error processing charts
Error: Process completed with exit code 1.

[RainbowMango]

/lgtm

[XiShanYongYe-Chang]

Hi @calvin0327 can you help take a look of Chart Lint?
/cc @calvin0327

[codecov-commenter]

Codecov Report

Merging #3644 (9cf3dc5) into master (b005d5b) will decrease coverage by 0.01%.
The diff coverage is n/a.

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@@            Coverage Diff             @@
##           master    #3644      +/-   ##
==========================================
- Coverage   55.68%   55.68%   -0.01%     
==========================================
  Files         222      222              
  Lines       21195    21195              
==========================================
- Hits        11803    11802       -1     
  Misses       8765     8765              
- Partials      627      628       +1     

Flag	Coverage Δ
unittests	55.68% <ø> (-0.01%)	⬇️

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

see 2 files with indirect coverage changes

[XiShanYongYe-Chang]

CI chart-lint-test error requires #3719 and #3721 to be merged first.

[RainbowMango]

/lgtm
/approve

[karmada-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: RainbowMango

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