Implement Monlet MVP stack and UI updates

server/monlet_server/services/notifiers/base.py

@@ -0,0 +1,17 @@
+from __future__ import annotations
+
+from dataclasses import dataclass
+from typing import Protocol
+
+
+@dataclass(frozen=True)
+class DeliveryResult:
+    ok: bool
+    permanent: bool = False
+    error: str | None = None
+
+
+class Notifier(Protocol):
+    name: str
+
+    async def deliver(self, event_type: str, payload: dict) -> DeliveryResult: ...