add __should_migrate flag handling

Author: Oleksandr Bazarnov

airbyte_cdk/connector_builder/connector_builder_handler.py

@@ -55,13 +55,22 @@ def get_limits(config: Mapping[str, Any]) -> TestLimits:
     max_streams = command_config.get(MAX_STREAMS_KEY) or DEFAULT_MAXIMUM_STREAMS
     return TestLimits(max_records, max_pages_per_slice, max_slices, max_streams)
 
+def should_migrate_manifest(config: Mapping[str, Any]) -> bool:
+    """
+    Determines whether the manifest should be migrated,
+    based on the presence of the "__should_migrate" key in the config.
+    
+    This flag is set by the UI.
+    """
+    return config.get("__should_migrate", False)
 
 def create_source(config: Mapping[str, Any], limits: TestLimits) -> ManifestDeclarativeSource:
     manifest = config["__injected_declarative_manifest"]
     return ManifestDeclarativeSource(
         config=config,
         emit_connector_builder_messages=True,
         source_config=manifest,
+        migrate_manifest=should_migrate_manifest(config),
         component_factory=ModelToComponentFactory(
             emit_connector_builder_messages=True,
             limit_pages_fetched_per_slice=limits.max_pages_per_slice,