fix(i18n): allow localization of early loading states via useStaticTranslation

[kheireddinebou]

Description

This PR fixes the issue where the early rendering states of the PDF viewer ("Initializing PDF engine...", "Initializing plugins...") are always displayed in English, regardless of the user's localized configuration.

Because loading indicators appear before the plugin system and dynamic translation hooks (useTranslations) are fully mounted, a static capability is needed to resolve simple translations from the configuration object synchronously.

Implementation Details

• Introduced a new hook/composable: useStaticTranslation inside @embedpdf/plugin-i18n.
• This hook takes the locales and defaultLocale from the config and manually traverses the translation keys statically.
• Refactored framework implementation examples (React, Vue, Svelte) to leverage this static resolver, successfully replacing hardcoded English texts with their localized counterparts on mount.
• Updated documentation (React, Vue, Svelte .mdx files) and the CHANGELOG.md to reflect the availability of the new useStaticTranslation function.

Related Issue

Closes #589

Pull Request Checklist

• Followed the existing code style
• Included comments in the code where necessary
• Updated documentation to reflect the new useStaticTranslation functionality
• Kept the pull request focused on this single fix
• Verified changes build and compile correctly (pnpm build:watch)

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