feat(research): streamline template details and enable bot versioning

backend/app/research_access/templates.py

@@ -10,23 +10,27 @@ from ..research.workspace_contracts import AssetWrite
 from .queries import item_summary
 
 
-async def create_template(db, args, principal):
-    """Save a new asset inside the caller's account-locked, idempotent transaction.
+async def create_template(db, args, principal, *, asset_id=None):
+    """Save a new asset or revision inside the caller's account-locked, idempotent transaction.
 
     Args contain the external model's TemplateSpec and local source item IDs.
     Return the versioned asset and theoretical combination count. Raise
     ResearchError for name conflicts or missing/incomplete research evidence.
     Stored evidence proves provenance, not profitability or platform eligibility;
     schema validation does not validate every expanded FASTEXPR combination.
+    Optional asset_id selects a version update guarded by args.expected_version;
+    a stale version raises HTTP 409 and cannot overwrite a historical revision.
     """
     from .service import ResearchError
 
     existing = await db.scalar(select(ResearchAsset).where(
         ResearchAsset.kind == "template", ResearchAsset.name == args.template.name,
+        ResearchAsset.id != asset_id if asset_id else True,
     ).order_by(ResearchAsset.id).limit(1))
     if existing:
         raise ResearchError("TEMPLATE_NAME_CONFLICT", "模板名称已存在，请使用新名称；此工具不覆盖已有模板",
                             affected_items=[{"template_id": existing.id, "version": existing.version}])
+    previous = await Assets(db).get(asset_id, expected_kind="template") if asset_id else None
     rows = (await db.execute(select(BacktestItem, BacktestResult).outerjoin(
         BacktestResult, BacktestResult.item_id == BacktestItem.id,
     ).where(BacktestItem.id.in_(args.source_item_ids)))).all()
@@ -48,12 +52,16 @@ async def create_template(db, args, principal):
         "admin_id": principal.admin_id,
         "source_items": [item_summary(*found[item_id]) for item_id in args.source_item_ids],
     }
+    if previous:
+        provenance["parent_template"] = {"id": asset_id, "version": args.expected_version}
     asset = await Assets(db).save(AssetWrite(
         kind="template", content=args.template.model_dump(mode="json"),
-    ), provenance=provenance)
+        version=args.expected_version if asset_id else None,
+    ), asset_id=asset_id, provenance=provenance)
     return {
         **asset, "template_id": asset["id"],
-        "combination_count": str(math.prod(len(v.values) for v in args.template.variables.values())),
+        "combination_count": (str(math.prod(len(v.values) for v in args.template.variables.values()))
+                              if all(v.values for v in args.template.variables.values()) else None),
         "validation": {"structure": "valid", "source_evidence": "recorded",
                        "expanded_candidates": "not_validated", "platform_semantics": "unknown"},
         "next_step": "在模板工坊选择固定输入及模拟设置，展开并核验候选，再确认批量回测。",