fix: bot no longer crashes container on invalid token

- bot.js: 5 retries with 5s delay on init, graceful fallback to null
- errorHandler.js: 5 retries on 404 (invalid token), stops polling after
  max retries but keeps process alive for admin panel
- config.js: BOT_TOKEN missing logs warning instead of process.exit
- index.js: bot handlers only registered when bot is available,
  admin panel always starts regardless of bot status

src/utils/errorHandler.js

@@ -1,5 +1,8 @@
 import logger from './logger.js';
 
+let pollingRetries = 0;
+const MAX_POLLING_RETRIES = 5;
+
 export default class ErrorHandler {
   static async handleError(bot, chatId, error, context) {
     logger.error({ err: error, context }, 'Error in handler');
@@ -8,6 +11,7 @@ export default class ErrorHandler {
       ? `Error: ${error.message}`
       : 'An error occurred. Please try again later.';
     
+    if (!bot) return;
     try {
       await bot.sendMessage(chatId, errorMessage);
     } catch (sendError) {
@@ -17,8 +21,32 @@ export default class ErrorHandler {
 
   static handlePollingError(error) {
     if (error.code === 'ETELEGRAM') {
+      const statusCode = error.response?.statusCode;
+      const description = error.response?.body?.description || '';
+
+      if (statusCode === 404 || description.includes('Not Found')) {
+        pollingRetries++;
+        logger.warn({ 
+          attempt: pollingRetries, 
+          maxRetries: MAX_POLLING_RETRIES,
+          statusCode,
+          description 
+        }, 'Invalid bot token (404). Will retry up to %d times.', MAX_POLLING_RETRIES);
+
+        if (pollingRetries >= MAX_POLLING_RETRIES) {
+          logger.error({ maxRetries: MAX_POLLING_RETRIES }, 
+            'Bot token is invalid after %d retries. Stopping polling. Admin panel continues running.', 
+            MAX_POLLING_RETRIES);
+        }
+        return;
+      }
+
+      if (statusCode === 401 || statusCode === 403) {
+        logger.error({ statusCode }, 'Authentication error. Stopping polling. Admin panel continues running.');
+        return;
+      }
+
       logger.error({ err: error }, 'Telegram API Error');
-      process.exit(1);
     } else {
       logger.error({ err: error }, 'Polling error');
     }