Run JUnit and Compile Task/Skill using Eclipse's compilation settings and dependencies

Copilot often compiles and runs JUnit test code using a Run In Terminal task/skill and benefits greatly from this by going back and forth with the unit tests failing sometimes a dozen times until it gets the tests right (relatable haha). This works very well for simple projects or once it figures out the compilation settings and JUnit invocation settings, dependencies, locations of source folders, the JUnit jar files internal to Eclipse, and source release targets and etc.c., often with a little manual help from me.

To me, this only feature missing for Copilot to be utterly amazing for complex coding projects beyond just little demos or purely source code editing without running tests to verify its own changes in existing mature projects.

There could be a Build Project task and a Run All JUnit Tests In Project task, upon which the plugin invokes directly within Eclipse.

This would also reduce the number of Run In Terminal tasks needed which are always a little concerning for a remote server to be running on your own machine even if you do vet its command strings. A Build Project task would need no security vetting, much like the Get Errors task right now, and the proposed Run JUnit task would be as secure or insecure as running the project's source code already is anyway.

Start by reviewing the existing Run In Terminal task/skill and the Get Errors task, which the issue identifies as relevant integration points. Then determine how Eclipse compilation settings, dependencies, source folders, release targets, and JUnit invocation are exposed. Done means the scope and behavior of Build Project and Run All JUnit Tests In Project tasks are defined, including their security boundaries.