fix(recipe): align preview default in api

.agents/logs/ai_changelog.md

@@ -1073,6 +1073,7 @@
 **Implemented**
 
 - Removed the per-recipe model-preview snapshot checkbox from the save dialog; the bounded sharing-friendly default is now internal, while legacy explicit `false` values remain compatible until a future Workflow Recipe global setting exists.
+- Aligned the backend recipe normalizer with the same default, so non-UI saves and imported recipes without a stored preference also receive portable model previews.
 - Added a prominent right-side active-notebook banner with the selected note name, timestamp, and current-state badge.
 - Added a short panel transition when switching parameter notebooks so the right pane visibly confirms the change.
 - Added request-token guards so a slow parameter-gallery response from the previous notebook cannot replace the newly selected notebook's gallery.

api/recipes.py

@@ -874,7 +874,7 @@ def _normalise_recipe(payload):
         presentation = {}
     if not isinstance(presentation, dict):
         raise ValueError("Invalid recipe presentation")
-    save_model_preview_snapshots = presentation.get("save_model_preview_snapshots", False)
+    save_model_preview_snapshots = presentation.get("save_model_preview_snapshots", True)
     if not isinstance(save_model_preview_snapshots, bool):
         raise ValueError("Invalid recipe presentation")
     cover_asset_id = presentation.get("cover_asset_id")