Test: Validate node "Copy src to clipboard" functionality via element menu in canvas

[Naseem77]

Title: validate copy to clipboard functionality for node
Preconditions: Browser is launched, and code graph home page is accessible.

Test Steps:

Navigate to the code graph home page.
Select a graph.
Open the details panel for a specific node and copy its source.
Verify the copied value matches the API response.

Expected Result: The copied source should match the API value for the selected node.