Unix **environ is never modified

[ascheman]

The Plugin manipulates the Java System environment (cf. System.getenv() API). Unfortunately, Java only caches the (initial) environment and modifications are never written back to the native Unix environment. Therefore, the (changed) environment is in particular never forwarded to spawned processes (e.g., in the IntelliJ Vale plugin).

The Plugin should implement a change to the native environment, e.g., via the Unix putenv library function.

At least a prominent warning should become part of the documentation, that the Plugin does not (yet) change the native process environment of IntelliJ.

[mattiasflodin]

I guess this explains why neither CLion nor RustRover will pick up environment variables when building the project? Which... kind of makes it impossible to build anything with dependencies on NixOS.