feat: expose workflow execution modes in editor

docs/workflows/WORKFLOW_DELIVERY_CHECKLIST.md

@@ -29,8 +29,8 @@
 - [x] Workflow context introduced
 - [x] Node outputs are persisted and reusable
 - [x] Graph runtime supports legacy fallback
-- [ ] `legacy`, `graph`, and `shadow` modes exist
-- Progress: Graph dispatch now persists retry/failure policy metadata per node, retries bridge-node failures within the configured attempt budget, and the production order-line dispatcher can opt into explicit graph mode with a hard fallback back to legacy dispatch if graph execution preparation or runtime fails.
+- [x] `legacy`, `graph`, and `shadow` modes exist
+- Progress: Workflow configs now normalize to an explicit execution mode, the editor exposes and persists `legacy`/`graph`/`shadow`, production order-line dispatch can opt into graph mode with hard fallback to legacy on graph failure, and shadow mode is stored safely while still deferring duplicate-safe parity execution to Phase 6.
 
 ### Phase 5
 

docs/workflows/WORKFLOW_IMPLEMENTATION_BACKLOG.md

@@ -74,7 +74,7 @@
 - `E4-T2` Refactor executor to process nodes against context and node outputs. `completed`
 - `E4-T3` Persist node-level run records, logs, timings, and outputs. `completed`
 - `E4-T4` Support retry and failure policies. `completed`
-- `E4-T5` Add execution mode switch: `legacy`, `graph`, `shadow`.
+- `E4-T5` Add execution mode switch: `legacy`, `graph`, `shadow`. `completed`
 - `E4-T6` Add hard fallback to legacy dispatch on graph failure. `completed`
 
 ## Epic 5: Editor Parity