fix(language-core): correct type narrowing from script to template

[KazariEX]

fix #4391

[pkg-pr-new[bot]]

commit: 195d735

vue-component-meta

``` pnpm add https://pkg.pr.new/vuejs/language-tools/vue-component-meta@4689 ```

vue-component-type-helpers

``` pnpm add https://pkg.pr.new/vuejs/language-tools/vue-component-type-helpers@4689 ```

@vue/language-core

``` pnpm add https://pkg.pr.new/vuejs/language-tools/@vue/language-core@4689 ```

@vue/language-plugin-pug

``` pnpm add https://pkg.pr.new/vuejs/language-tools/@vue/language-plugin-pug@4689 ```

@vue/language-server

``` pnpm add https://pkg.pr.new/vuejs/language-tools/@vue/language-server@4689 ```

@vue/language-service

``` pnpm add https://pkg.pr.new/vuejs/language-tools/@vue/language-service@4689 ```

vue-tsc

``` pnpm add https://pkg.pr.new/vuejs/language-tools/vue-tsc@4689 ```

@vue/typescript-plugin

``` pnpm add https://pkg.pr.new/vuejs/language-tools/@vue/typescript-plugin@4689 ```

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[johnsoncodehk]

LGTM, thanks!