Then open a Julia file in a Julia project (a Project.toml or JuliaProject.toml must be defined). Then run M-x dap-debug. It will ask you for a run template. Choose Julia Run Configuration.
The use-package statements were required.
Then after calling dap-debug and choosing JRC I get the following messages:
Failed to connect to localhost:43941 with error message make client process failed: Connection refused, :name, Julia Debug, :buffer, nil, :host, localhost, :service, 43941, :nowait, nil, :noquery, nil, :tls-parameters, nil, :coding, no-conversion [138 times]
Debug session process exited with status: deleted
I have GNU Emacs 30.0.92 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.43, cairo version 1.18.0), package management with Elpaca.