fix(bot): issue #142 — language selection on first contact (Products/message in sleep mode)

- keyboard.products in sleep mode: language_set=0 -> language keyboard first, then AI in chosen language
- message handler in sleep mode: same language_set check before AI
- AI context verified: chat_sessions history (max 20) + LANGUAGE_INSTRUCTIONS[lang] in system prompt
- 30 tests pass

src/index.js

@@ -15,6 +15,7 @@ import leadService from './services/leadService.js';
 import UserService from './services/userService.js';
 import { resetUserContext } from './utils/messageUtils.js';
 import { tryAcquireLock, pruneLocks } from './utils/callbackLock.js';
+import { tForUser, LANGUAGE_NAMES, AVAILABLE_LANGUAGES } from './i18n/index.js';
 
 setInterval(() => {
     pruneLocks();
@@ -65,6 +66,17 @@ if (bot && botAvailable) {
             // Если сообщение не обработано роутером и чатбот включён — отправить в ИИ
             if (!dispatched && msg.text && await chatbotService.isChatbotEnabled()) {
                 const user = msg.__user || await UserService.getUserByTelegramId(msg.from.id);
+                // Первый контакт: сначала выбор языка
+                if (!user?.language_set) {
+                    const keyboard = {
+                        inline_keyboard: AVAILABLE_LANGUAGES.map(code => [{
+                            text: LANGUAGE_NAMES[code],
+                            callback_data: `set_language_${code}`
+                        }])
+                    };
+                    await bot.sendMessage(msg.chat.id, tForUser('en')('bot.language_select'), { reply_markup: keyboard });
+                    return;
+                }
                 const lang = user?.language || 'en';
                 const result = await chatbotService.sendToChatbot({
                     sessionId: msg.from.id,

src/router/routes.js

@@ -7,6 +7,7 @@ import { resetUserContext } from '../utils/messageUtils.js';
 import chatbotService from '../services/chatbotService.js';
 import leadService from '../services/leadService.js';
 import UserService from '../services/userService.js';
+import { tForUser, LANGUAGE_NAMES, AVAILABLE_LANGUAGES } from '../i18n/index.js';
 
 import userHandler from '../handlers/userHandlers/userHandler.js';
 import userPurchaseHandler from '../handlers/userHandlers/userPurchaseHandler.js';
@@ -89,6 +90,17 @@ export function registerRoutes() {
         // Магазин на паузе — сразу переключаем на ИИ-диалог, убираем меню
         if (await chatbotService.isSleepMode()) {
             const user = msg.__user || await UserService.getUserByTelegramId(msg.from.id);
+            // Первый контакт: сначала выбор языка
+            if (!user?.language_set) {
+                const keyboard = {
+                    inline_keyboard: AVAILABLE_LANGUAGES.map(code => [{
+                        text: LANGUAGE_NAMES[code],
+                        callback_data: `set_language_${code}`
+                    }])
+                };
+                await bot.sendMessage(msg.chat.id, tForUser('en')('bot.language_select'), { reply_markup: keyboard });
+                return;
+            }
             const lang = user?.language || 'en';
             const result = await chatbotService.sendToChatbot({
                 sessionId: msg.from.id,