🧹 Modernize type hints in balancer/core.py

[alfieprojectsdev]

This change modernizes the type hints in balancer/core.py by replacing the deprecated List and Dict from the typing module with the built-in list and dict types, as per PEP 585. This improvement enhances code readability and maintainability while leveraging modern Python 3.9+ features. Additionally, unused imports from typing were removed and local __pycache__ artifacts were cleaned up.

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PR created automatically by Jules for task 5643490081544463411 started by @alfieprojectsdev

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