fix(hydration): avoid hydration mismatch on style variables with falsy values

[yangxiuxiu1115]

fix #12439

[pkg-pr-new[bot]]

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@vue/compiler-core

``` pnpm add https://pkg.pr.new/@vue/compiler-core@12442 ```

@vue/compiler-dom

``` pnpm add https://pkg.pr.new/@vue/compiler-dom@12442 ```

@vue/compiler-sfc

``` pnpm add https://pkg.pr.new/@vue/compiler-sfc@12442 ```

@vue/compiler-ssr

``` pnpm add https://pkg.pr.new/@vue/compiler-ssr@12442 ```

@vue/reactivity

``` pnpm add https://pkg.pr.new/@vue/reactivity@12442 ```

@vue/runtime-core

``` pnpm add https://pkg.pr.new/@vue/runtime-core@12442 ```

@vue/runtime-dom

``` pnpm add https://pkg.pr.new/@vue/runtime-dom@12442 ```

@vue/server-renderer

``` pnpm add https://pkg.pr.new/@vue/server-renderer@12442 ```

@vue/shared

``` pnpm add https://pkg.pr.new/@vue/shared@12442 ```

vue

``` pnpm add https://pkg.pr.new/vue@12442 ```

@vue/compat

``` pnpm add https://pkg.pr.new/@vue/compat@12442 ```

commit: 8ce63aa

[github-actions[bot]]

Size Report

Bundles

File	Size	Gzip	Brotli
runtime-dom.global.prod.js	100 kB	37.9 kB	34.2 kB
vue.global.prod.js	158 kB	57.8 kB	51.4 kB

Usages

Name	Size	Gzip	Brotli
createApp (CAPI only)	47.2 kB	18.3 kB	16.8 kB
createApp	55.2 kB	21.3 kB	19.5 kB
createSSRApp	59.3 kB	23.1 kB	21 kB
defineCustomElement	60.1 kB	22.9 kB	20.8 kB
overall	69.1 kB	26.5 kB	24.1 kB

[edison1105]

The isRenderableAttrValue should be applied here to filter values, aligning with SSR behavior. https://github.com/vuejs/core/blob/c4312f9c715c131a09e552ba46e9beb4b36d55e6/packages/runtime-dom/src/helpers/useCssVars.ts#L97