Fix unique ID collision and via_device race conditionFix unique ID collision and via_device race condition

[garethmo]

Fixes #114 and #61

Changes

• Unique ID Collision: Modified helpers.py to check against unique_id instead of entity_id when filtering new entities.
• Via Device Error: Modified __init__.py to use a two-pass approach for device setup, ensuring all devices exist before linking them with via_device.

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