Add support for QR code task

src/task.py

@@ -30,6 +30,7 @@ class TaskType(Enum):
     TEXT = "text"
     IMAGE = "image"
     CUT = "cut"
+    QR = "qr"
 
 
 class PrintTask(ABC):
@@ -67,6 +68,15 @@ class TextTask(PrintTask):
     def get_print_data(self):
         return {"txt": self.content, "sign": self.signature}
 
+class QRTask(TextTask):
+    """This task prints a QR-Code, the signature is ignore and is always the content itself"""
+    def __init__(self, content):
+        super().__init__(content, signature="")
+        self.content = content
+        self.signature = content
+
+    def get_print_data(self):
+        return {"txt": self.content, "sign": self.signature}
 
 class ImageTask(PrintTask):
     """