Project Rules

Localization (required)

Every change or addition must include an update to js/i18n.js: review and update the translations and localization behavior affected by the change.

Every user-facing string must go through js/i18n.js. Never hardcode Thai or English UI text in HTML or JS.

Use data-i18n, data-i18n-placeholder, data-i18n-title, data-i18n-alt or data-i18n-aria-label in index.html.
Use t('key', { ...vars }) for strings rendered from JavaScript (including innerHTML templates).
Add every new key to MODAL_AND_TOOL_TRANSLATIONS in js/i18n.js for both th and en. Other locales intentionally fall back to English through t(), so they do not need duplicate entries.
When a language changes, dynamic content must refresh. Call the render function from applyTranslations() (for example renderEquipTargetDisplay() and renderAvatarAssignGrid()).
Keep every import of i18n.js on the same ?v= query string so the browser uses a single module instance. Bump it whenever js/i18n.js changes.

When css/styles.css or js/app.js changes, bump its ?v= query string in index.html.

Do not modify README.md or the untracked docs/ folder unless the task explicitly asks for it.