Remove unused test dependencies #103

[traktion]

Resolves #103.

This PR addresses the issue of unused test dependencies and warnings in mod tests blocks.

Changes include:

• Added #![cfg_attr(test, allow(unused_imports, unused_variables, dead_code))] to src/lib.rs.
• Added #![cfg_attr(test, warn(unused_imports, unused_variables, dead_code))] to all child mod.rs files to re-enable warnings at the module level.
• Cleaned up unused imports and variables specifically within mod tests blocks.
• Incremented the patch version in Cargo.toml.
• Added a spec file for the issue.

Verified that cargo test passes with 196 tests and minimal warnings outside of mod tests blocks (or where expected).