feat: Add Telegram bot with group support

- Full Telegram bot implementation for Lightning Jackpot
- Commands: /start, /buy, /tickets, /wins, /address, /jackpot, /help
- Lightning invoice generation with QR codes
- Payment polling and confirmation notifications
- User state management (Redis/in-memory fallback)
- Group support with admin settings panel
- Configurable draw announcements and reminders
- Centralized messages for easy i18n
- Docker configuration included

telegram_bot/src/handlers/start.ts

@@ -0,0 +1,68 @@
+import TelegramBot from 'node-telegram-bot-api';
+import { stateManager } from '../services/state';
+import { logger, logUserAction } from '../services/logger';
+import { getMainMenuKeyboard, getCancelKeyboard } from '../utils/keyboards';
+import { messages } from '../messages';
+
+/**
+ * Handle /start command
+ */
+export async function handleStart(bot: TelegramBot, msg: TelegramBot.Message): Promise<void> {
+  const chatId = msg.chat.id;
+  const userId = msg.from?.id;
+  
+  if (!userId) {
+    await bot.sendMessage(chatId, messages.errors.userNotIdentified);
+    return;
+  }
+
+  logUserAction(userId, 'Started bot', {
+    username: msg.from?.username,
+    firstName: msg.from?.first_name,
+  });
+
+  try {
+    // Check if user exists
+    let user = await stateManager.getUser(userId);
+    
+    if (!user) {
+      // Create new user
+      user = await stateManager.createUser(
+        userId,
+        msg.from?.username,
+        msg.from?.first_name,
+        msg.from?.last_name
+      );
+    }
+
+    // Welcome message
+    await bot.sendMessage(chatId, messages.start.welcome, { parse_mode: 'Markdown' });
+
+    // Check if lightning address is set
+    if (!user.lightningAddress) {
+      await bot.sendMessage(chatId, messages.start.needAddress, { 
+        parse_mode: 'Markdown',
+        reply_markup: getCancelKeyboard(),
+      });
+      
+      await stateManager.updateUserState(userId, 'awaiting_lightning_address');
+    } else {
+      // Show main menu
+      await bot.sendMessage(
+        chatId,
+        messages.start.addressSet(user.lightningAddress),
+        {
+          parse_mode: 'Markdown',
+          reply_markup: getMainMenuKeyboard(),
+        }
+      );
+      
+      await stateManager.updateUserState(userId, 'idle');
+    }
+  } catch (error) {
+    logger.error('Error in handleStart', { error, userId });
+    await bot.sendMessage(chatId, messages.errors.startAgain);
+  }
+}
+
+export default handleStart;