feat: move translations to singlefile

[Its-Just-Nans]

Related to #233

Sorry if there are mistakes :/

[Copilot]

Pull Request Overview

This PR centralizes Japanese translation strings by creating a single translations file and replacing hardcoded Japanese text throughout the codebase. This improves maintainability and consistency of the localization system.

• Creates a centralized menuTranslations object containing all Japanese translation strings
• Replaces hardcoded Japanese strings across components and templates with references to the translation object
• Updates icon components to use translated accessibility labels

Reviewed Changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
website/src/translations.tsx	Creates centralized translation object with all Japanese strings
website/src/components/ui/common/TranslationStatusAlert.tsx	Replaces hardcoded status messages with translation references
website/src/components/ui/common/TableOfContents.tsx	Updates table of contents title to use translations
website/src/components/ui/common/SiteTitle.tsx	Updates site title components and fixes href to root
website/src/components/ui/common/SiteNoticeBanner.tsx	Replaces banner text with translation references
website/src/components/ui/common/SearchWindow.tsx	Updates search window labels with translations
website/src/components/ui/common/Header.tsx	Replaces header text and aria labels with translations
website/src/components/ui/Tooltip.tsx	Updates tooltip content with translation references
website/src/components/ui/FunctionParameters.tsx	Replaces parameter-related text with translations
website/src/components/ui/FunctionDisplay.tsx	Updates function display text with translations
website/src/components/templates/*.tsx	Updates template text with translation references
website/src/components/icons/*.tsx	Updates icon accessibility titles with translations

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[3w36zj6]

I think managing translations in TSX is a good approach.

Please take a look at the proposal in #233 (comment). With simple templates, it is difficult to handle different word orders properly. So how about setting a pure function that returns TSX as the value? With this method, translators can freely markup the content in any word order they need.

And, it is preferable that each individual phrase is managed as a single key-value pair, rather than splitting into smaller strings.

[3w36zj6]

Thank you for your work. I’ll review it later.