i18n support — serve non-English-speaking end clients

Hi, Today all user-facing strings are hardcoded in English iirc. Two levels would unlock non-English markets, by priority: 1. OUTBOUND MESSAGES & SEEDED DEFAULTS (critical, small scope): the ~25-30 hardcoded outbound messages (missed-call SMS, welcome email/SMS presets, WhatsApp starter templates, booking/quote emails, review request, AI receptionist greetings) plus seeded defaults (contact form labels, "30-minute consultation", deal currency USD, default timezone). These are sent to our clients' own customers — an English SMS from a French tradesman's business breaks the product promise. A per-sub-account or per-agency locale setting for these templates/seeds would be enough. 2. APP UI (larger, second step): extracting UI strings into locale files (next-intl or similar) so agencies can ship the dashboard in their market's language. Also worth noting: "Reply STOP to opt out" is US CTIA wording — For example, France requires "STOP au 36180", other markets differ. A localizable compliance string would cover this. Best,