[7.0] Generate Eclipse run configurations using Slime Launcher

[Jonathing]

ForgeGradle 7 currently works by registering tasks to run the game using Slime Launcher. Work needs to be done to better support adding run configurations for Eclipse

Eclipse

Eclipse Buildship is unable to hook the debugger into JavaExec tasks (see eclipse-buildship/buildship#1130). As a result, for ForgeGradle 7.0, I believe the solution is to create a successor to genEclipseRuns that invokes Slime Launcher to generate the output Eclipse launch files.

Slime Launcher should be responsible for this as it is the one that modifies the classpath, downloads assets, and handles other pre-bootstrap tasks. Think of it as an effective prepareEclipseRuns but for generating the file to be used by Eclipse.

I'll be testing this thoroughly with @LexManos as it is a key requirement for both ForgeGradle 7 and ForgeDev 7.

For all other IDEs: please use your IDE's native method of calling the Gradle run task in debug mode.

[Jonathing]

I've edited the title and description of this issue to demonstrate its new goal. I will also be creating an issue on SlimeLauncher with the task to create Eclipse run configurations.

[Jonathing]

Closed by merging of #1005.