Emit an event when a verifier stake is returned

[RUKAYAT-CODER]

Background

Verifier stake deposits and slashes emit events (verifier_stake_deposited, verifier_stake_slashed), but return_verifier_stake does not emit anything, so off-chain consumers cannot observe a returned stake. Add and emit a verifier_stake_returned event.

Files to modify (2)

• contracts/earn-quest/src/events.rs
• contracts/earn-quest/src/escrow.rs

Acceptance Criteria

• Implemented across the listed files
• Unit/integration tests added or updated and passing
• No regression; follows project coding standards

[Ranjeet2063]

Hello! I'd like to work on this issue.

Execution Plan for Emit an event when a verifier stake is returned:

• Clean Implementation: Deliver an idiomatic solution for Emit an event when a verifier stake is returned adhering strictly to EarnQuestOne/stellar_Earn's architecture.
• Automated Tests: Provide full test coverage asserting both edge cases and core workflows.
• Clean Git Hygiene: Atomic conventional commits with zero merge conflicts.

Why assign me?

• Proven Proof-of-Work: Implement Wallet Connection System #1 contributor on Mova Store (28 merged Web3 PRs) and official ElizaOS contributor.
• Fast Turnaround: Dedicated to shipping a tested, production-grade PR within 12–24 hours.
• Zero Maintainer Burden: Self-documenting code with green CI and tests included so you don't spend time debugging.

Looking forward to clearing this off your backlog—please assign to me!