[TIME-TRAVEL] [FEAT] Add 'Resource Usage' metrics to snapshots

[dotandev]

Description

Developers need to see how much gas/budget each step 'stole'.

Requirements

• Read Host::get_budget() before and after host calls.
• Store the CPU and Memory consumption delta in the snapshot metadata.
• Export these metrics in the snapshot JSON/Bincode.

Acceptance Criteria

• Snapshots show precise resource usage per step.
• Metrics align with the official Soroban budget limits.

Estimated File Changes: 2 (simulator/src/types.rs, simulator/src/host.rs)

[ayomideadeniran]

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

I'm a full-stack developer and I'd like to take this issue.
I understand the requirements and will follow the existing project structure, keep the implementation clean, and include proper tests where applicable.

ETA: 1–3 days (depending on scope)
Portfolio: https://knightsdev-portfolio.vercel.app/

ℹ️ Repo Maintainers: To accept this application, review their application or assign @ayomideadeniran to this issue.

[drips-wave]

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

🧑‍💻 @ayomideadeniran: 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

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊