Add a circuit-breaker guard to the escrow contract's release paths

[Meshmulla]

Summary

The escrow contract (soroban/src/escrow_contract.rs) handles asset locking and release — the highest-value flow in the system. We already have a circuit_breaker module; integrating it into escrow would let us halt withdrawals instantly if an anomaly or exploit is detected, limiting blast radius.

What we'd like

• Add a circuit-breaker / pause check to the sensitive escrow entry points (release/withdraw)
• When tripped, those paths should cleanly revert with a clear error while safe read paths keep working
• An authorized role can trip and reset the breaker

Where to look

• soroban/src/escrow_contract.rs — the flows to guard
• soroban/src/circuit_breaker.rs and submission_pause.rs — existing pause/breaker primitives to reuse
• soroban/src/acl.rs — access control for who may trip/reset

Acceptance criteria

• Release/withdraw paths honor the circuit breaker and revert with a descriptive error when tripped
• Only an authorized role can trip or reset the breaker
• Read-only queries remain available while paused
• Tests cover the tripped and reset states

Notes

Reuse the existing breaker module rather than adding a parallel mechanism — consistency matters for auditing.

[Favouromale]

Hi, I'd like to work on this issue.

I understand the goal is to protect the escrow's release and withdrawal paths with the existing circuit-breaker mechanism, while keeping read-only operations available when the breaker is tripped.

My approach would be to:

• Review escrow_contract.rs to identify all release/withdraw entry points that need to be guarded.
• Inspect the existing circuit_breaker, submission_pause, and ACL implementations so the escrow integration follows the repository's existing patterns rather than introducing a separate pause mechanism.
• Add the circuit-breaker check at the appropriate point in the sensitive paths and return a clear, descriptive error when the breaker is active.
• Ensure only the existing authorized role can trip and reset the breaker.
• Keep read-only queries unaffected while the breaker is active.
• Add tests covering the normal, tripped, and reset states, including authorization checks and ensuring protected operations cannot proceed while paused.

[grantfox-oss]

🦊 GrantFox — @Favouromale has been assigned to this issue as part of the Third Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #6)
2. Your PR will be reviewed by the stellar-kracken maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Third Campaign campaign!

@Favouromale's PR #28 was approved and merged by @Meshmulla.

🏆 @Favouromale: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (83 total points). Track your full progress on GrantFox.

👏 Great work, @Favouromale! Keep contributing to stellar-kracken.