Replace column-based email template languages (subject_en/subject_de) with
a normalized email_template_translations table where each language is a row.
This allows adding new languages without schema changes.
- Add migration 075 to create email_template_translations table, migrate
existing EN/DE data, and seed NL/PT/RU for customer-facing templates
- Update processTemplate() to query translations table with fallback chain
(requested lang -> en -> first available), with legacy column fallback
- Restructure admin email API to return/accept translations object format
- Update frontend EmailConfigPage with dynamic 5-language tabs, translation
count badges, and copy-from-language feature for empty translations
- Add Dutch to default language dropdown in general settings
- Add Dutch to clientAccessI18n and password security messages in emails
- Expand email domain detection for NL/BE/BR/PT/RU domains
- Add email i18n keys (copyFrom, noTranslation, etc.) across all 5 locales
Paul Nothaft
f50d7c0c51