docs: fix indicator for current page and hydration mismatch

[warmthsea]

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After:

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[pkg-pr-new]

commit: c40ee5b

create-slidev

pnpm add https://pkg.pr.new/slidevjs/slidev/create-slidev@1842

@slidev/client

pnpm add https://pkg.pr.new/slidevjs/slidev/@slidev/client@1842

create-slidev-theme

pnpm add https://pkg.pr.new/slidevjs/slidev/create-slidev-theme@1842

@slidev/parser

pnpm add https://pkg.pr.new/slidevjs/slidev/@slidev/parser@1842

@slidev/cli

pnpm add https://pkg.pr.new/slidevjs/slidev/@slidev/cli@1842

@slidev/types

pnpm add https://pkg.pr.new/slidevjs/slidev/@slidev/types@1842

Open in Stackblitz

[KermanX]

<LinkInline link="guide/" /> is displayed as Why Slidev instead of Getting Started (although the target URL is correct)