[docs] fix http client related sections

Author: capcom6

README.md

@@ -133,8 +133,7 @@ async function initializeJWTClient() {
     // Initialize client with JWT token (empty string for login, token for passwordOrToken)
     const jwtClient = new Client(
         "", // Empty string for login when using JWT
-        jwtToken, // JWT token
-        httpFetchClient
+        jwtToken // JWT token
     );
 
     return jwtClient;
@@ -291,17 +290,15 @@ The `Client` class accepts the following constructor arguments:
 ```typescript
 const api = new Client(
     process.env.ANDROID_SMS_GATEWAY_LOGIN!,  // Username
-    process.env.ANDROID_SMS_GATEWAY_PASSWORD!,  // Password
-    httpFetchClient
+    process.env.ANDROID_SMS_GATEWAY_PASSWORD!  // Password
 );
 ```
 
 **JWT Authentication:**
 ```typescript
 const api = new Client(
     "",  // Empty string for login when using JWT
-    jwtToken,  // JWT token
-    httpFetchClient
+    jwtToken  // JWT token
 );
 ```
 
@@ -450,7 +447,7 @@ For more details, see the [`domain.ts`](./src/domain.ts).
 
 ## 🌐 HTTP Clients
 
-The library doesn't come with built-in HTTP clients. Instead, you should provide your own implementation of the `HttpClient` interface:
+The library comes with fetch-based built-in HTTP client. You can provide your own implementation of the `HttpClient` interface:
 
 ```typescript
 interface HttpClient {