[engine] Support Custom Rules via YAML DSL (User-defined assertions)

[Gbangbolaoluwagbemiga]

Context

Allow users to define proprietary guidelines as AST matchers in YAML.

[Zarmaijemimah]

@Zarmaijemimah has applied to work on this issue as part of the Stellar Wave Program's 3rd wave.

I can handle this issue and will love to work on it please kindly assign thank you.

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[Nanle-code]

@Nanle-code has applied to work on this issue as part of the Stellar Wave Program's 3rd wave.

let me work on this

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[drips-wave]

Congratulations, @Nanle-code! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on March 30, 2026.

🧑‍💻 @Nanle-code: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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🌊 Happy Wave 🌊

[drips-wave]

This issue has been marked as completed by a Drips Wave moderator for @Nanle-code as part of the Stellar Wave Program's 3rd Wave 🥳

Moderator's reason: [Auto-assessed] The contributor (Nanle-code) implemented the requested YAML DSL for custom rules in PR #484, which has been merged. The PR includes the YAML parsing logic, AST matchers, and example documentation specifically requested in the issue.

😎 @Nanle-code: You earned 200 Points for completing this issue! After the current Wave ends, you'll be eligible for a percentage of the Wave's reward pool based on the percentage of total points you've earned. Learn more here.

🧑‍💻 Repo maintainers: How'd the contributor do? Leave a review to share your experience working with them.

ℹ️ Note: This issue was marked complete via moderation. Points were issued even though the GitHub issue remains open.