feat(automations): add event trigger params

surfsense_backend/app/automations/triggers/builtin/event/params.py

@@ -0,0 +1,23 @@
+"""``EventTriggerParams`` — params for the ``event`` trigger type."""
+
+from __future__ import annotations
+
+from typing import Any
+
+from pydantic import BaseModel, ConfigDict, Field
+
+
+class EventTriggerParams(BaseModel):
+    model_config = ConfigDict(extra="forbid")
+
+    event_type: str = Field(
+        ...,
+        min_length=1,
+        description="Event type to listen for.",
+        examples=["document.indexed"],
+    )
+    filter: dict[str, Any] = Field(
+        default_factory=dict,
+        description="JSON filter matched against the event payload.",
+        examples=[{"document_type": "FILE"}],
+    )