Add comprehensive unit and integration test coverage for all contracts

[devJaja]

Summary

Test coverage varies across contracts. agent_registry has extensive snapshot-backed tests, but other contracts have minimal or no test coverage. All contracts need comprehensive unit tests and integration tests before mainnet deployment.

Priority

P1 — Required for mainnet deployment confidence.

Files to work on

smart-contracts/contracts/*/src/tests.rs
smart-contracts/tests/integration/

Requirements

• Audit test coverage for each contract using cargo tarpaulin or similar
• Add unit tests for all public functions in:
  • agent_bidding: bid submission, reveal phase, winner selection, reputation weighting
  • agent_marketplace: listing, search, purchase, delivery confirmation
  • dispute_resolution: filing, evidence, voting, resolution
  • task_store: create, status transitions, history queries
  • upgrade-manager: proposal, approval, execution, rollback
• Add integration tests that exercise cross-contract interactions
• Add edge case tests: zero amounts, maximum batch sizes, unauthorized access, duplicate operations
• Add snapshot tests for event emissions
• Ensure all tests pass with cargo test --workspace

Acceptance Criteria

• Every public function has at least 2 unit tests (happy path + error case)
• Test coverage ≥ 80% for all contracts (line coverage)
• Integration tests cover cross-contract flows (registry + bidding + payment)
• Edge cases tested: zero amounts, empty vectors, duplicate IDs, unauthorized calls
• All tests pass with cargo test --workspace
• No #[ ignore ] tests without a documented reason and tracking issue

[achebejohnpaul]

Am a full-Stack Engineer focused on frontend, backend, APIs, automation, and modern web technologies. Passionate about solving real-world problems, contributing to open source, and delivering clean, scalable, review-ready solutions.