Looking at the error you got seems very telling:
Executing task: make WORKDIR=/workspaces/TWO_FILES/appconfig_0/work/TWO_FILES install <
make: *** No rule to make target ‘install’. Stop.
In short the extension invokes make install in order to install the compiled binaries to your project workdir. However the Makefile you copied from Eclipise probably didn’t have a rule for “install” which is why you get this error. You’ll need to probably slightly modify your Makefile to accommodate this.
As a reference for what to change/add create a fresh C/C++ Makefile based project with our extension. Then inspect the default Makefile in the fresh project. Notice how the “install” rule is defined there.
Best Regards,
Jeremias