feat: add /devices endpoint

dto.py

@@ -0,0 +1,17 @@
+class Device:
+    def __init__(self, access_key, device_type, name):
+        self.access_key = access_key
+        self.device_type = device_type
+        self.name = name
+
+
+    def to_dict(self):
+        return {
+                'access_key': self.access_key,
+                'type': self.device_type,
+                'name': self.name
+               }
+
+    def convert(device_from_db) -> Device:
+        return Device(*device_from_db)
+