feat(invoice-escrow): implement duration & error handling

[devfoma]

This PR implements three important tasks for Devops and Contract Logic:

closes #73

• Configures cargo-tarpaulin and uploads Code Coverage artifacts (Cobertura XML & LCOV) to GitHub Actions in .github/workflows/coverage.yml.

closes #74

• Adds a --dry-run flag support to scripts/deploy.sh to safely simulate deployment logging without making RPC transactions or deploying smart contracts.

closes #75

• Implements partial refund functionality when cancel_escrow is invoked by the seller in contracts/invoice-escrow/src/lib.rs.
• Extends error handling with CancelNotAllowed in contracts/invoice-escrow/src/errors.rs.
• Updates type documentation for clarity in contracts/invoice-escrow/src/types.rs.
• Modifies testing logic and adds test coverage for refund execution upon cancellation of partially funded escrows in contracts/invoice-escrow/src/test.rs.

Checklist

• All implementation tasks cleanly addressed.
• Code compiles without warnings/errors.
• Tested locally and tests pass successfully.
• Tested script with --dry-run and correctly mocks smart contract functions.

[drips-wave]

@devfoma Great news! 🎉 Based on an automated assessment of this PR, the linked Wave issue(s) no longer count against your application limits.

You can now already apply to more issues while waiting for a review of this PR. Keep up the great work! 🚀

Learn more about application limits

[chizzy192]

Hi @devfoma, please perform the following updates on your PR:

1. Rename your PR title from Feature/issue 73 74 75 to standard conventional commit format (e.g. feat(invoice-escrow): implement issues 73, 74, and 75 duration & error handling) to satisfy the Validate PR Title & Description CI requirement.
2. Fetch the latest dev branch and rebase (git rebase dev) to resolve line conflicts in contracts/invoice-escrow/src/{errors.rs, lib.rs, types.rs}.
3. Verify that your updates to .github/workflows/coverage.yml and scripts/deploy.sh pass shell linting and local cargo test -p invoice-escrow execution.