feat(queries): implementation of regal for linting rego files

[ArturRibeiro-CX]

Integrate Regal Linter for Rego Files in KICS

This PR introduces the Regal linter to enforce best practices, maintainability, and consistency in Rego files within KICS.
Since Rego is extensively used for queries, adding this linter helps ensure high-quality and standardized code.

Reason for Proposed Changes

• Improve code quality, maintainability, and consistency by adding a structured linter;
• Ensure best practices in Rego queries while allowing future refinements via configuration.

Proposed Changes

• Add Regal Linter (v1.0.0) as part of the CI pipeline;
• Include a configuration file (assets/.regal/config.yml) to define linter rules;
• Run the linter on Rego files in the assets/ directory during PRs.

Note: This PR only integrates the linter, separate PRs will address individual linting issues.

Continuation of #7295

References

• Styra official documentation
• Styra setup regal linter github action github page
• Styra regal github page

I submit this contribution under the Apache-2.0 license.

[github-actions]

KICS version: v2.1.4

Category Results CRITICAL 0 HIGH 0 MEDIUM 0 LOW 0 INFO 0 TRACE 0 TOTAL 0	Metric Values Files scanned 1 Files parsed 1 Files failed to scan 0 Total executed queries 47 Queries failed to execute 0 Execution time 0