CI/CD environment setup and dependency verification

[Mehulantony]

Verified local environment setup for the OSS SLU Mouser project and documented dependency installation and test execution findings.

Key points:

1. All dependencies installed successfully under Python 3.13 except playsound (known incompatibility).
2. Tests run but show import errors due to relative path resolution (shared, databases).
3. Application launches successfully via python main.py.
4. Created docs/env_investigation.md detailing findings, validation, and recommendations for CI/CD setup.

Impact:

1. No production code modified.
2. Established foundation for stable CI/CD configuration and future test automation.