fix: canvas color issue and refactor Sass removal & rgbToHsl optimization

[quarksb]

1. fix: color of canvas initial error
2. refactor: rm sass due to sass error(Deprecation Warning [legacy-js-api]: The legacy JS API is deprecated and will be removed in Dart Sass 2.0.0.)
3. refactor: optimize rgbToHsl function for improved readability and performance

[Copilot]

Pull Request Overview

This PR addresses multiple issues including canvas color initialization problems, removes Sass dependencies due to deprecation warnings, and optimizes the rgbToHsl function. The changes modernize the codebase by migrating from Sass to vanilla CSS and improving color coordinate calculations.

• Fixed canvas color initialization errors with proper pointer positioning and resize handling
• Removed Sass dependency and converted SCSS syntax to vanilla CSS
• Optimized rgbToHsl function using Math.max/min and cleaner logic flow

Reviewed Changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/core/helper/converters.ts	Optimized rgbToHsl function with cleaner algorithm and better performance
src/components/Vue3ColorPicker.vue	Major refactor: added pointer positioning logic, lifecycle management, and converted SCSS to CSS
src/components/PickerWrap.vue	Removed empty SCSS style block
src/components/PickerMenu.vue	Removed empty SCSS style block
src/components/PickerHue.vue	Removed empty SCSS style block
src/components/OpacityBar.vue	Removed empty SCSS style block
src/components/GradientBar.vue	Removed empty SCSS style block
src/components/ColorInputMenu.vue	Removed empty SCSS style block
package.json	Removed sass dependency and updated TypeScript version

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[Copilot]

The switch statement comparing floating-point numbers with strict equality may fail due to precision issues. Use a tolerance-based comparison or restructure the logic to avoid direct floating-point equality checks.

Suggested change

	switch (max) {
	case nr:
	h = (ng - nb) / delta;
	break;
	case ng:
	h = 2 + (nb - nr) / delta;
	break;
	default:
	h = 4 + (nr - ng) / delta;
	break;
	const EPSILON = 1e-10;
	if (Math.abs(max - nr) < EPSILON) {
	h = (ng - nb) / delta;
	} else if (Math.abs(max - ng) < EPSILON) {
	h = 2 + (nb - nr) / delta;
	} else {
	h = 4 + (nr - ng) / delta;

[Copilot]

The magic number 5 for retry count should be extracted as a named constant to improve maintainability and make the retry limit configurable.