refactor(automations): move agent_task to builtin and restructure dispatch

surfsense_backend/app/automations/dispatch/inputs.py

@@ -0,0 +1,43 @@
+"""Merge and validate the inputs a run starts with."""
+
+from __future__ import annotations
+
+from typing import Any
+
+import jsonschema
+
+from app.automations.persistence.models.trigger import AutomationTrigger
+from app.automations.schemas.definition.envelope import AutomationDefinition
+
+from .errors import DispatchError
+
+
+def prepare_inputs(
+    definition: AutomationDefinition,
+    trigger: AutomationTrigger,
+    runtime_inputs: dict[str, Any] | None,
+) -> dict[str, Any]:
+    """Merge ``trigger.static_inputs`` over ``runtime_inputs``, then validate.
+
+    Static inputs win on key collision.
+    """
+    merged = {**(runtime_inputs or {}), **(trigger.static_inputs or {})}
+    return validate_inputs(definition, merged)
+
+
+def validate_inputs(
+    definition: AutomationDefinition, inputs: dict[str, Any]
+) -> dict[str, Any]:
+    """Validate ``inputs`` against the definition's optional declared schema.
+
+    No declared schema → pass through unchanged so runtime keys (``fired_at``,
+    ``last_fired_at``, ...) still reach the template context. A declared schema
+    that the inputs violate is surfaced as ``DispatchError``.
+    """
+    if definition.inputs is None or not definition.inputs.schema_:
+        return inputs
+    try:
+        jsonschema.validate(instance=inputs, schema=definition.inputs.schema_)
+    except jsonschema.ValidationError as exc:
+        raise DispatchError(f"inputs: {exc.message}") from exc
+    return inputs