Client tests don't work with changes in Mojo 24.3

[saviorand]

Since Mojo 24.3 main() functions inside packages are no longer supported.

This was used in /tests/run.mojo to run a test suite (which is just one client test for now). The client test worked by running a server in another process (terminal tab) via mojo lightbug.🔥, then running mojo tests/run.mojo.

Now I tried to work around the issue, and moved the test suite to lightbug.🔥, which is where the main function for the whole package lives. I'm using the ability to pass a key-value to mojo run command like so: mojo -D "TEST" lightbug.🔥.

Currently this doesn't work, getting a bunch of compile errors. I'm assuming this has more to do with the Mojo client code than with the new way to run the main() function, but if anyone has ideas would appreciate.