refactor(automations): extract dispatch_run; move manual adapter under triggers/manual/dispatch.py

surfsense_backend/app/automations/dispatch/errors.py

@@ -0,0 +1,7 @@
+"""Dispatch errors raised when a fire request cannot be turned into a run."""
+
+from __future__ import annotations
+
+
+class DispatchError(Exception):
+    """A dispatch could not proceed (missing trigger, invalid inputs, ...)."""