[CONTRACTS] Add integration test for execute with session key signature

[wheval]

Summary

Test full execute path: session key signs canonical payload, contract accepts.

Background

Medium-effort, independently implementable task. Not part of Stellar Wave program tracking.

Scope

• contracts/account/src/lib.rs

Files to create / modify

Add test_execute_session_key_end_to_end in test module.

Example implementation

let sig = sign_payload(&session_sk, &payload);
client.execute(&to, &fn, &args, &nonce, &Some(session_pk), &Some(sig));

Acceptance criteria

• Happy path passes
• Wrong signature rejected
• Expired key rejected
• Snapshot updated

Difficulty

Medium

Labels

enhancement, medium, contract, security

[Richardkingz2019]

@Richardkingz2019 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

I would like to work on this issue and I shall deliver promptly on this with qualitaively feedback

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Richardkingz2019 to this issue.

[david87131]

@david87131 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi Maintainer Can I work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @david87131 to this issue.

[drips-wave]

Congratulations, @david87131! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @david87131: 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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