refactor: simplify distillation data layout

designir-pipeline/agents/reconstruction-agent.md

@@ -8,7 +8,7 @@ geometry.
 
 ## Allowed inputs
 
-- One private evidence packet produced by the ingestion service.
+- One private evidence packet from `runs/evidence/`.
 - The user modification request.
 - Promoted generalized experience.
 - The DesignIR schema and supported operation vocabulary.
@@ -24,7 +24,7 @@ geometry.
 
 ## Required output
 
-Write one `*.designir.json` containing:
+Write one `runs/designir/*.designir.json` containing:
 
 - family and reconstruction status;
 - coordinate system and datums;
@@ -46,4 +46,5 @@ If the vocabulary is insufficient, emit
 Request `isolated-rebuild`. Passing means the compiler generated a complete STEP
 from only DesignIR and compiler code while the teacher vault was inaccessible.
 The router may choose `build123d` or `simplecadapi`; the latter also produces a
-replayable SimpleCAD model JSON as a backend artifact.
+replayable SimpleCAD model JSON as a backend artifact. Put rebuild artifacts in
+`runs/rebuilt/`.