feat(cli): Add cluster health status command with show-health functionality

[sanjay7178]

Description

fixes #65

Comprehensive Health Checks:

• Node Status: Verifies all nodes in the cluster are ready
• Pod Status: Checks pod health in kubeslice-related namespaces (kubeslice-controller, kubeslice-system)
• Component Status: Validates core KubeSlice components:
  • Controller clusters: kubeslice-controller, cert-manager
  • Worker clusters: kubeslice-operator, spire-server, spire-agent

Output formats

• JSON format (-o json) for programmatic usage
• YAML format (-o yaml) for structured output
• Status icons: ✓ Healthy, ✗ Unhealthy, ? Unknown

Usage

# Check health of a specific cluster
kubeslice-cli show-health cluster <CLUSTER-NAME> -c <TOPOLOGY-PATH>

# Check health of all clusters in the configuration
kubeslice-cli show-health cluster -A  -c <TOPOLOGY-PATH>

How Has This Been Tested?

This is the tests are tested on my two gke clusters , one in us-east1 and us-central1 regions also as far now there's a issue with calico networking in controller part it seems #83 , so as far these are the tests i've performed via kubeslice-cli

Checklist:

• The title of the PR states what changed and the related issues number (used for the release note).
• Does this PR requires documentation updates?
• I've updated documentation as required by this PR.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have tested it for all user roles.
• I have added all the required unit test cases.

Does this PR introduce a breaking change?

YES

[sanjay7178]

PTAL and kindly review @priyupadhyay @priyupadhyay @narmidm

[sanjay7178]

@gourishkb made the changes at 7d67fd1