Refactor to move the HTTP-handling part to its own module
Refactor to move the debugger guts to its own module
Allow the listen port to be specified in an env var
Rename the test helper module
Allow specifying the port and testharness flag in import
Use the port gathered at import() instead of the env var
If running in the test harness, remember the parent PID and exit if it's gone
Working test of loading the debugger
Add a test for step in