Merge pull request #103 from elsa-workflows/copilot/create-migration-guide-v2-to-v3

Add comprehensive V2 to V3 migration guide (DOC-001)

Author: sfmskywalker

SUMMARY.md

@@ -28,6 +28,7 @@
 
 ## Guides
 
+* [V2 to V3 Migration Guide](guides/migration-v2-to-v3.md)
 * [Authentication & Authorization](guides/authentication.md)
 * [HTTP Workflows](guides/http-workflows/README.md)
   * [Programmatic](guides/http-workflows/programmatic.md)