feat(api): add backend

routes and WebSockets

services/api/app/schemas/events.py

@@ -0,0 +1,9 @@
+from datetime import datetime
+from pydantic import BaseModel
+
+
+class LoudEvent(BaseModel):
+    time: datetime
+    rms_db: float
+    frequency_hz: int
+    duration_sec: float | None = None