Add CI/CD Workflows and Tests

[Natuworkguy]

I have added a comprehensive CI/CD pipeline to the project, including:

1. Linting Workflow: Uses ruff to ensure code quality and adherence to style guides.
2. Testing Workflow: Runs unit tests using pytest across Python versions 3.10, 3.11, and 3.12.
3. Build Workflow: Verifies that the package can be built successfully using the build module.
4. Unit Tests: Added a set of unit tests in tests/test_ai.py covering core logic like environment variable handling, history trimming, and command parsing.
5. Development Dependencies: Introduced requirements-dev.txt to manage tools used during development and CI.

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PR created automatically by Jules for task 12668641507374188450 started by @Natuworkguy

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