feat: Add request timeout and Redis duplicate update prevention

- Added `Request::$timeout` and `Request::setClientTimeout` to control Guzzle client timeout.
- Added Redis update de-duplication in `Telegram::processUpdate`.
- Added `Telegram::setRedis` for injecting Redis instance.
- Added `Telegram::$update_retention_time` and `Telegram::setUpdateRetentionTime` to configure de-duplication TTL.
- Updated README.md with instructions.
- Default request timeout is set to 60 seconds.
- Duplicate updates are cached in Redis for 60 seconds (default) and return a fake success response.

Author: google-labs-jules[bot]

README.md

@@ -114,6 +114,37 @@ You can also access the Redis instance statically from anywhere in your project:
 $redis = \Longman\TelegramBot\Telegram::getRedis();
 ```
 
+### 3. Prevent Duplicate Updates
+
+Enabling Redis also activates the built-in duplicate update prevention mechanism. This is useful when the bot receives the same update multiple times due to timeouts or retries from Telegram.
+
+When Redis is enabled:
+1.  The library checks if the `update_id` exists in Redis.
+2.  If it exists, the update is ignored, and a fake success response is returned to Telegram to stop retries.
+3.  If it doesn't exist, the `update_id` is stored in Redis with a retention time (TTL) of 60 seconds.
+
+You can customize the retention time (in seconds):
+
+```php
+// Set retention time to 120 seconds
+Longman\TelegramBot\Telegram::setUpdateRetentionTime(120);
+```
+
+---
+
+## ⚙️ Advanced Configuration
+
+### Request Timeout
+
+To prevent your server from hanging on slow Telegram API requests (e.g., cURL error 28), you can set a custom timeout for the HTTP client. The default timeout is 60 seconds.
+
+```php
+use Longman\TelegramBot\Request;
+
+// Set request timeout to 30 seconds
+Request::setClientTimeout(30);
+```
+
 ---
 
 ## 🔐 Webhook Secret Token

src/Telegram.php

@@ -41,6 +41,13 @@ class Telegram
     /** @var \Redis|null */
     private static $redis_connection;
 
+    /**
+     * Update retention time in Redis (in seconds)
+     *
+     * @var int
+     */
+    private static $update_retention_time = 60;
+
     /**
      * Telegram API key
      *
@@ -566,7 +573,7 @@ public function processUpdate(Update $update): ServerResponse
                 return new ServerResponse(['ok' => true, 'result' => true], $this->bot_username);
             }
             // Store the update ID in Redis with a TTL of 60 seconds (matching the default timeout).
-            self::$redis_connection->setex($redis_key, 60, '1');
+            self::$redis_connection->setex($redis_key, self::$update_retention_time, '1');
         }
 
         if (is_callable($this->update_filter)) {
@@ -1151,6 +1158,17 @@ public static function setRedis(\Redis $redis): void
         self::$redis_connection = $redis;
     }
 
+    /**
+     * Set the update retention time in Redis
+     *
+     * @param int $seconds
+     * @return void
+     */
+    public static function setUpdateRetentionTime(int $seconds): void
+    {
+        self::$update_retention_time = $seconds;
+    }
+
     /**
      * Get the shared Redis client instance.
      *