Don't use dust UTXOs in txns

[victorkirov]

🔘 PR Type

What kind of change does this PR introduce?

• [x] Bugfix

📜 Background

We were using confirmed Dust UTXOs as inputs for txns before unconfirmed large UTXOs (e.g. change).

Additionally, we weren't filtering out unconfirmed UTXOs when selecting them for inscription commit txns, so the fee estimate logic was using different logic to the final commit txn build logic causing inconsistencies.

🔄 Changes

Does this PR introduce a breaking change?

• [x] Yes, Incompatible API changes
• [ ] No, Adds functionality (backwards compatible)
• [ ] No, Bug fixes (backwards compatible)

Changes:

• When selecting UTXOs, if a fee rate has not been specified, we use the regular fee rate to filter out dust UTXOs

Impact:

• We would no longer use dust UTXOs for txns

✅ Review checklist

Please ensure the following are true before merging:

• [ ] Code Style is consistent with the project guidelines.
• [ ] Code is readable and well-commented.
• [ ] No unnecessary or debugging code has been added.
• [ ] Security considerations have been taken into account.
• [ ] The change has been manually tested and works as expected.
• [ ] Breaking changes and their impacts have been considered and documented.
• [ ] Code does not introduce new technical debt or issues.

[github-actions[bot]]

Test this PR with npm i --save-exact @secretkeylabs/xverse-core@4.1.0-b84b9a5