fix: the check of some transitions are missed

[luzhuang]

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• [ ] Tests for the changes have been added (for bug fixes / features)
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Summary by CodeRabbit

• New Features

  • Improved animation state transitions with fixed timing for better consistency.
  • Added new methods to calculate fixed start and end times for animation clips.
  • Enhanced management of transitions based on exit time properties.

• Bug Fixes

  • Resolved inconsistencies in event timing during playback.

• Refactor

  • Streamlined transition handling logic for clarity and efficiency.
  • Improved organization of transition management within the AnimatorStateTransitionCollection class.