refactor(modal): allow to disable dialog animation

[spliffone]

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[gemini-code-assist]

Code Review

This pull request introduces a global flag to disable modal animations, which is a good improvement for accessibility and performance on low-end devices. The implementation correctly uses a helper to check for the global setting.

However, the current implementation is incomplete. The global animation setting is only applied to the animation timings controlled by animationTime(), but not to the CSS-based fade animations or the backdrop animation logic.

I've added a couple of suggestions to refactor the logic into a reusable isAnimated property. Adopting this suggestion and using the new property consistently in showBackdrop() and the component's template (si-modal.component.html) will fix the issue and make the code cleaner.

[github-actions]

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[github-actions]