feat: update style of mail

src/application/contracts/i_sender.py

@@ -4,5 +4,13 @@ from abc import ABC, abstractmethod
 class ISender(ABC):
 
     @abstractmethod
-    async def send(self, to: str, subject: str, body: str, plain: str | None = None) -> None:
+    async def send(
+        self,
+        to: str,
+        subject: str,
+        body: str,
+        plain: str | None = None,
+        *,
+        inline_png: tuple[str, bytes] | None = None,
+    ) -> None:
         raise NotImplementedError