Implement dynamic pet resizing and interactive proportional scaling

[mx57]

Implemented a comprehensive pet resizing feature (range 50-250px) integrated with SettingsDialog, ConfigManager, and PetWindow. Scaled all procedural animations (jumping in happy state, head bobbing in eating state) and petting interaction boundaries proportionally to the window dimensions. Implemented missing procedural rendering states for playing and shaking in AnimationManager.

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PR created automatically by Jules for task 6936853786751040535 started by @mx57

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