Add IPFS link to recipe S-expression display

- Show ipfs://... link next to recipe S-expression header
- Links to ipfs.io gateway for viewing the raw S-expression

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/routers/runs.py

@@ -179,6 +179,7 @@ async def get_run(
         # Try to load the recipe to show the plan
         plan = None
         plan_sexp = None  # Native S-expression if available
+        recipe_ipfs_cid = None
         recipe_id = run.get("recipe")
         if recipe_id and len(recipe_id) == 64:  # Looks like a hash
             try:
@@ -189,6 +190,8 @@ async def get_run(
                     # Use native S-expression if available (code is data!)
                     if recipe.get("sexp"):
                         plan_sexp = recipe["sexp"]
+                    # Get IPFS CID for the recipe
+                    recipe_ipfs_cid = recipe.get("ipfs_cid")
 
                     # Build steps for DAG visualization
                     dag = recipe.get("dag", {})
@@ -329,6 +332,7 @@ async def get_run(
             dag_elements=dag_elements,
             output_media_type=output_media_type,
             plan_sexp=plan_sexp,
+            recipe_ipfs_cid=recipe_ipfs_cid,
             active_tab="runs",
         )