Implement the sync state calculation for the kubernetes livestate plugin

[Warashi]

What this PR does:

as title

Why we need it:

We want to support DriftDetection feature with k8s plugin

Which issue(s) this PR fixes:

Part of #5363

Does this PR introduce a user-facing change?: No

• How are users affected by this change:
• Is this breaking change:
• How to migrate (if breaking change):

[codecov]

Codecov Report

Attention: Patch coverage is 41.55844% with 45 lines in your changes missing coverage. Please review.

Project coverage is 25.69%. Comparing base (317a7c9) to head (9d2d19c).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
.../app/pipedv1/plugin/kubernetes/livestate/plugin.go	41.55%	44 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5676      +/-   ##
==========================================
- Coverage   25.73%   25.69%   -0.04%     
==========================================
  Files         478      474       -4     
  Lines       51400    50981     -419     
==========================================
- Hits        13230    13102     -128     
+ Misses      37166    36888     -278     
+ Partials     1004      991      -13     

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[Warashi]

reference implementation is here

pipecd/pkg/app/piped/driftdetector/kubernetes/detector.go

Lines 385 to 422 in 57c48c1

	func makeSyncState(r *provider.DiffListResult, commit string) model.ApplicationSyncState {
	if r.NoChange() {
	return model.ApplicationSyncState{
	Status: model.ApplicationSyncStatus_SYNCED,
	ShortReason: "",
	Reason: "",
	Timestamp: time.Now().Unix(),
	}
	}
	total := len(r.Adds) + len(r.Deletes) + len(r.Changes)
	shortReason := fmt.Sprintf("There are %d manifests not synced (%d adds, %d deletes, %d changes)", total, len(r.Adds), len(r.Deletes), len(r.Changes))
	if len(commit) >= 7 {
	commit = commit[:7]
	}
	var b strings.Builder
	b.WriteString(fmt.Sprintf("Diff between the defined state in Git at commit %s and actual state in cluster:\n\n", commit))
	b.WriteString("--- Actual (LiveState)\n+++ Expected (Git)\n\n")
	details := r.Render(provider.DiffRenderOptions{
	MaskSecret: true,
	MaskConfigMap: true,
	MaxChangedManifests: 3,
	// Currently, we do not use the diff command to render the result
	// because Kubernetes adds a large number of default values to the
	// running manifest that causes a wrong diff text.
	UseDiffCommand: false,
	})
	b.WriteString(details)
	return model.ApplicationSyncState{
	Status: model.ApplicationSyncStatus_OUT_OF_SYNC,
	ShortReason: shortReason,
	Reason: b.String(),
	Timestamp: time.Now().Unix(),
	}
	}