fix: JFXRippler 可能无法覆盖整个控件

[CiiLu]

例：版本下载页面

[Copilot]

Pull request overview

该 PR 旨在修复 JFXRippler 在某些较大控件（如版本下载页面）上水波纹效果半径不足、无法覆盖整个控件的问题。

Changes:

• 调整 computeRippleRadius() 的计算方式：由“对角线长度 + 上限裁剪 + 额外裕量”改为“仅对角线长度”。

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

computeRippleRadius() now returns the exact diagonal, but the ripple grow animation only scales to 0.9 while the mouse is pressed (see Ripple.inAnimation target scale). This means the visible radius while pressed will be 0.9 * diagonal and can still fail to reach the far corner until mouse release, which undermines the goal of covering the whole control. Consider either (a) restoring a safety margin (e.g., divide by 0.9 and add a small padding) or (b) changing the in-animation target scale to 1 so the computed radius is actually reached.

Suggested change

	return Math.sqrt(Math.pow(control.getLayoutBounds().getWidth(), 2) + Math.pow(control.getLayoutBounds().getHeight(), 2));
	// compute the control diagonal
	double width = control.getLayoutBounds().getWidth();
	double height = control.getLayoutBounds().getHeight();
	double diagonal = Math.sqrt(width * width + height * height);
	// compensate for the in-animation max scale (0.9) and add a small padding
	double safetyScale = 1.0 / 0.9;
	double padding = 2.0;
	return diagonal * safetyScale + padding;

[Copilot]

Using Math.pow(x, 2) here is unnecessary overhead compared to x * x, and this change also makes RIPPLE_MAX_RADIUS unused in this class (it was previously referenced in this method). Consider switching back to multiplication and either removing the unused constant or repurposing it (e.g., as an optional upper bound via the styleable ripplerRadius property) to avoid dead code.

Suggested change

	return Math.sqrt(Math.pow(control.getLayoutBounds().getWidth(), 2) + Math.pow(control.getLayoutBounds().getHeight(), 2));
	double width = control.getLayoutBounds().getWidth();
	double height = control.getLayoutBounds().getHeight();
	return Math.sqrt(width * width + height * height);