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

[ArturRibeiro-CX]

This PR integrates the Regal linter for Rego files in KICS to support query maintanance, reusability and best practices. As KICS uses Rego extensively to build queries, adding a linter helps ensuring consistency and quality across our codebase.

Thanks to the contributors who initiated the discussions and provided input for this addition. 🥳 🙌

Closes #6774
Closes #505

Reason for Proposed Changes

• Improve code quality, maintainability and consistency by applying the Regal linter to Rego files;
• Implement linter rules that follow best practices while leaving flexibility to refine rules over time (through rego_config.yaml);

Proposed Changes

• Add Regal Linter (v1.0.0) for Rego files;
• Create a configuration file ( rego_config.yaml) to specify which linter rules to enforce or ignore;
• Update Rego queries to to address linting issues.

Documentation Links:

• Styra Documentation
• Action setup-regal Official Github Page
• Regal Official Github Page
• Styra-Renovating Rego Blog Post

I submit this contribution under the Apache-2.0 license.

[github-actions]

KICS version: v2.1.3

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 48 Queries failed to execute 0 Execution time 0

[gitguardian]

⚠️ GitGuardian has uncovered 2 secrets following the scan of your pull request.

Please consider investigating the findings and remediating the incidents. Failure to do so may lead to compromising the associated services or software components.

🔎 Detected hardcoded secrets in your pull request

GitGuardian id	GitGuardian status	Secret	Commit	Filename
14477467	Triggered	Generic Password	8fa67a6	assets/libraries/common.rego	View secret
14477466	Triggered	Generic Password	8fa67a6	assets/libraries/common.rego	View secret

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