fix(tests): update actor_examples count to 7 after subplan example

Refs: #198

features/actor_examples.feature

@@ -653,13 +653,14 @@ Feature: Actor YAML examples validation
 
   Scenario: Verify all example files exist
     Given the examples/actors directory
-    Then there should be exactly 6 example YAML files
+    Then there should be exactly 7 example YAML files
     And the example files should include "simple_llm.yaml"
     And the example files should include "llm_with_tools.yaml"
     And the example files should include "tool_collection.yaml"
     And the example files should include "simple_graph.yaml"
     And the example files should include "graph_workflow.yaml"
     And the example files should include "hierarchical_workflow.yaml"
+    And the example files should include "strategy_with_subplan.yaml"
 
   Scenario: Verify all examples are documented
     Given the documentation file "docs/reference/actors_examples.md"