🧪 Add tests for Thinker class

[johnstrand]

🎯 What: Added tests for the Thinker class Update method to address missing coverage.
📊 Coverage: Covered initialization, time tracking, OnThink invocation, and zero/negative intervals.
✨ Result: Improved test coverage and reliability for GameUtils.Entity.Thinker.

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PR created automatically by Jules for task 11988656884990163142 started by @johnstrand

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