Detector: Integer info-loss in event data casts

[Gbangbolaoluwagbemiga]

Epic: Detectors (wave 3)

Summary

Add a static-analysis detector for integer info-loss in event data casts.

Background & Problem

Casting a wider value down when publishing event data silently truncates what indexers see.

Acceptance Criteria

• Flags narrowing casts in event payloads.
• Suggests emitting full-width.

Technical Notes

Follow the rule pattern in tooling/sanctifier-core/src/rules/ with an insta golden snapshot.

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Filed as part of the mainnet-readiness & world-class roadmap. Scope is intentionally small enough for one focused PR; comment to claim.

[anidroid1184]

Hi! I would like to claim this issue to add the static-analysis detector for integer info-loss. Following the acceptance criteria, I will implement the rule under tooling/sanctifier-core/src/rules/ to flag narrowing casts in event payloads and include an insta golden snapshot test. Can you please assign it to me?

[Gbangbolaoluwagbemiga]

GM @anidroid1184 , you are assigned, ensure all CI pipeline passes.

[grantfox-oss]

🦊 GrantFox — @anidroid1184 has been assigned to this issue as part of the Official Campaign | FWC26 campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #804)
2. Your PR will be reviewed by the Centurylong maintainers

Good luck! Track your progress on GrantFox.