feat(docs): Add auto-generation and KatibClient out-of-cluster guide

[NarayanaSabari]

What this PR does / why we need it:

1. Implements automated documentation generation for Kubeflow SDK
2. Adds comprehensive guide for using KatibClient outside Kubernetes clusters with Service Account tokens
3. Covers real-world use cases: EC2, CI/CD pipelines, and development machines

Which issue(s) this PR fixes:

Fixes #50

Related issues:

Relates to kubeflow/katib#2046

Special notes for your reviewer:

• Auto-docs generation workflow ready for SDK components
• KatibClient examples verified against actual Katib SDK implementation (v1beta1)
• Includes both TrainerClient and KatibClient configuration patterns
• SSL certificate handling for self-signed certificates
• Practical troubleshooting for common errors (401/403, SSL, connection issues)

Checklist:

• Auto-docs generation implementation
• Documentation follows restructuredText format
• Code examples tested against Katib codebase
• Includes troubleshooting guidance
• References related GitHub issues

Here is the deployed link: https://kf-sdk.readthedocs.io/en/latest/

[google-oss-prow]

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