feat: run fixed research pipelines within durable budgets

backend/app/research/experiments.py

@@ -121,14 +121,18 @@ class Experiments:
             validation["status"] = "needs_review"
         return validation
 
-    async def create(self, body, kind="template", extra_evidence=None):
+    async def create(self, body, kind="template", extra_evidence=None, *, parent_snapshots=None):
         asset = await self.assets.get(body.asset_id, body.version, "template") if body.asset_id else None
         template = TemplateSpec.model_validate(asset["content"]) if asset else body.template
         scope = scope_of(body.settings)
         if template.scope and template.scope.model_dump() != scope:
             raise HTTPException(422, "模板适用范围与候选设置不同")
         snapshots, fields = await self.inputs(body.input_ids, scope)
-        parents = await self.parents(body.parent_alpha_ids, body.parent_experiment_ids)
+        parents = (
+            parent_snapshots
+            if parent_snapshots is not None
+            else await self.parents(body.parent_alpha_ids, body.parent_experiment_ids)
+        )
         variables = {}
         for name, variable in template.variables.items():
             if variable.kind == "field":