fix: Correct YAML format in demo_loop_timer.yaml

- Remove invalid 'version' field
- Restructure to match DevAll YAML schema (graph at top level)
- Move start/end nodes to end of graph block
- Validation now passes: 'Workflow OK. Design is valid.'

yaml_instance/demo_loop_timer.yaml

@@ -1,10 +1,4 @@
-version: 0.4.0
 graph:
-  start:
-    - StandardWriter
-  end:
-    - StandardFinalizer
-    - PassthroughFinalizer
   id: loop_timer_comprehensive_demo
   description: |
     Comprehensive LoopTimer demonstration with both standard and passthrough modes.
@@ -22,8 +16,8 @@ graph:
     The Passthrough Timer Gate allows messages through immediately, maintains a parallel 
     feedback loop (PassthroughCritic → PassthroughWriter), and after 2 minutes emits a 
     time limit message before becoming transparent.
-  is_majority_voting: false
   log_level: INFO
+  is_majority_voting: false
   nodes:
     # ===== STANDARD MODE BRANCH =====
     - id: StandardWriter
@@ -135,3 +129,9 @@ graph:
     # Timer gate output (immediate passthrough + timer message at 2 min)
     - from: Passthrough Timer Gate
       to: PassthroughFinalizer
+
+  start:
+    - StandardWriter
+  end:
+    - StandardFinalizer
+    - PassthroughFinalizer