[WIP]: Added enums linter

[krishagarwal278]

Description

This PR introduces a new enums linter to enforce best practices for enumerated fields in Kubernetes APIs.

The new linter, enums, achieves the following:

• Documents Enum Fields: Enforces use of type aliases with +enum markers instead of plain strings. Ensures enum values are explicitly documented in OpenAPI schemas with clear justifications for their purpose.
• Prevents Regressions: Validates that enum fields match documented patterns. Prevents undocumented or accidental changes to enum naming conventions and type definitions.
• Improves API Quality: Enforces PascalCase naming for enum values (e.g., "PhasePending"). Ensures thoughtful consideration for enum field design, improving schema validation and generated client type safety.
• The linter is disabled by default and supports an allowlist for special cases like command-line tool names.

[k8s-ci-robot]

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This pull-request has been approved by: krishagarwal278
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