feat(i18n): add pseudolocalization support for testing

[yslpn]

Add Pseudolocalization Support

This PR adds pseudolocalization support to @valibot/i18n for testing internationalization.

What is Pseudolocalization?

Pseudolocalization is a testing technique that replaces text with accented characters and special markers to help identify i18n issues:

• Accented characters test Unicode support and font rendering
• Increased text length (~30% longer) tests UI layout with longer translations
• Boundary markers [!!! ... !!!] help identify truncated text
• Template variables like ${issue.received} are preserved

Changes

• Added pseudo.ts with pseudolocalized error messages
• Updated types.ts to include 'pseudo' language code
• Updated build scripts (build-npm.ts, build-jsr.ts) to include pseudolocalization
• Updated package.json to export pseudo locale files

// Before (English)
Invalid type: Expected string but received 123

// After (Pseudolocalized)  
[!!! ẋẋẋ Ìñvàlìd týpé: Éxpéçţéd string büţ réçéìvéd 123 ẋẋẋ !!!]

Examples in other libs:

Lingui - https://lingui.dev/guides/pseudolocalization
Dayjs - https://github.com/iamkun/dayjs/blob/dev/src/locale/x-pseudo.js

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Project	Deployment	Preview	Comments	Updated (UTC)
valibot	Ready	Preview	Comment	Aug 17, 2025 0:23am

[Copilot]

Pull Request Overview

This PR adds pseudolocalization support to the @valibot/i18n package to help test internationalization features by replacing English text with accented characters and special markers.

• Added pseudolocalized error messages with accented characters and boundary markers
• Updated the type system to include 'pseudo' as a valid language code
• Integrated pseudolocalization into the build pipeline and package exports

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
packages/i18n/src/types.ts	Added 'pseudo' language code to the Language type union
packages/i18n/src/pseudo.ts	Implemented comprehensive pseudolocalized error messages for all validation types
packages/i18n/scripts/build-npm.ts	Added pseudo import and included it in the languages array for npm build
packages/i18n/scripts/build-jsr.ts	Added pseudo import and included it in the languages array for JSR build
packages/i18n/package.json	Added extensive package exports for all pseudo locale files
packages/i18n/jsr.json	Added pseudo exports and exclude patterns for JSR configuration
packages/i18n/.gitignore	Added pseudo directory to gitignore

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