future-private: add place order request

examples/PlaceOrderExample.php

@@ -165,3 +165,4 @@ try {
  * BITUNIX_API_SECRET=your-api-secret
  * BITUNIX_LANGUAGE=en-US
  */
+

src/Requests/PlaceOrderRequestContract.php

@@ -50,3 +50,4 @@ interface PlaceOrderRequestContract
         ?string $slOrderPrice = null
     ): ResponseInterface;
 }
+

tests/PlaceOrderTest.php

@@ -235,3 +235,4 @@ it('can handle different effect types', function () {
         ))->not->toThrow(Exception::class);
     }
 });
+