fix(useScroll): use mutationObserver to update arrivedState when the DOM is changed

[andylou0102]

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As the VueUse audience continues to grow, we have been inundated with an overwhelming number of feature requests and pull requests. As a result, maintaining the project has become increasingly challenging and has stretched our capacity to its limits. As such, in the near future, we may need to slow down our acceptance of new features and prioritize the stability and quality of existing functions. Please note that new features for VueUse may not be accepted at this time. If you have any new ideas, we suggest that you first incorporate them into your own codebase, iterate on them to suit your needs, and assess their generalizability. If you strongly believe that your ideas are beneficial to the community, you may submit a pull request along with your use cases, and we would be happy to review and discuss them. Thank you for your understanding.

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Description

close #4265

Additional context

My test below ( forked from haykkh )

https://stackblitz.com/edit/vitejs-vite-vthxo9?file=src%2FuseScrollTest.js

[antfu]

We should introduce an options for this behavior, like:

vueuse/packages/core/useCssVar/index.ts

Lines 12 to 16 in e8c5db5

	/**
	* Use MutationObserver to monitor variable changes
	* @default false
	*/
	observe?: boolean

[andylou0102]

Ok, I will sent a new PR to handle this.