chore: Update mix.exs to include mix_test_watch dependency for TDD

[njausteve]

Title

Add mix_test_watch dependency and configuration to support Test-Driven Development (TDD)

Type of Change

• New feature

Description

This pull request introduces the mix_test_watch dependency to support Test-Driven Development (TDD). A new configuration file (config/config.exs) was added to specify tasks for running tests and static analysis (credo). The mix.exs file was updated to reflect the new configuration path, and the lockfile was adjusted to include the new dependency. These changes aim to improve the developer experience by enabling automatic testing and analysis when files are modified during development.

Testing

• Verified that mix_test_watch triggers tests and static analysis on file changes.
• Ensured that the terminal output clears before each test run.
• Confirmed compatibility with existing tools (credo and sobelow).

Impact

This update affects the development workflow by introducing continuous testing and static analysis. While it enhances the feedback cycle, it could introduce minor performance overhead during development.

Additional Information

No major risks identified; however, there may be a minor learning curve for developers unfamiliar with mix_test_watch.

Checklist

• My code adheres to the coding and style guidelines of the project.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.