I know I've seen the idea of breaking up AGS into command line tools given at least a passing reference in the past, but has anyone ever made a serious attempt to do this? ...decoupling the editor from the compiler/linker, and so on? I think the advantages are obvious (and have been discussed: automated builds, editor independence, all leading to easier-to-implement cross platform development environments, and so on). Has anyone gone beyond the conception stage with this idea?
All I know is there is a limited progress in rewriting the old and 'dirty' C++ code to C# classes that compile the game. In theory that could at least help having a cleaner code to start with.
A while ago, I was looking to implement better compiler warnings but stopped when I found an old implementation of compiler warnings behind the flag "SCOPT_SHOWWARNINGS". Setting the flag (which nothing does) will output those warnings to the console. This suggests to me that the compiler might once have been a standalone command line tool (or possibly even DOS-based tool at that time). There's also evidence of old intermediate formats like "game28.dta" in the code. I don't know enough about AGS history to comment further, but approaching it as a case of restoring old functionality might make the task easier.
EDIT: Sorry to not really answer the question. I don't think anyone has gone beyond the conception stage *recently* with this idea.