Add event emission completeness tests aligned with events_complete.md

[Baskarayelu]

Description

Add tests asserting events are emitted for critical transitions (invoice, bids, escrow, settlement, disputes) and match documented schemas, to protect off-chain indexing.

Requirements and context

• Must be secure, tested, and documented
• Should be efficient and easy to review

Suggested execution

• Fork the repo and create a branch
• git checkout -b feature/event-completeness-tests
• Implement changes
• Write contract: quicklendx-contracts/src/events.rs + emit calls across modules
• Write comprehensive tests: quicklendx-contracts/src/test_events.rs and/or integration tests
• Add documentation: update docs/contracts/events_complete.md if schema changes
• Include NatSpec-style comments (Rust doc comments on public items)
• Validate security assumptions (no sensitive payloads; deterministic emission)

Test and commit

• Run tests
• cd quicklendx-contracts && cargo test --verbose
• Include test output and security notes

Example commit message

test: assert event emission for critical protocol transitions

Guidelines

• Minimum 95 percent test coverage
• Clear documentation
• Timeframe: 96 hours

[N-i-xx]

@N-i-xx has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

Dear maintainer
Please assign me this issue

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[drips-wave]

Congratulations, @N-i-xx! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on April 29, 2026.

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