debug without (re-)compile

[GitMensch]

I've now tested this extension with some bigger programs where the source is on a slow network share. The result: the compilation part takes quite some time, but that is "ok" because out of the scope of this extension.

The part that is really bad: when using "restart" the complete source is re-compiled for no good reason (I didn't changed anything, just wanted to start debugging from scratch). Please fix that.

In general it would be nice to only compile upon explicit request - maybe have mutliple targets "recompile and debug" + "debug" - or even better: only do the compilation part if the expected binary is either missing or has a time-stamp older than the sources (as this is "unknown" for copybooks it may be reasonable to be able to adjust this behavior in an extension setting or to still provide two targets).

At least when attaching to a process there's zero use in recompile (the binary is currently in use so not even possible to be recreated, cobc will likely error because of that - at least on some systems).