Improve out-of-the box experience

[ReinhardKeil]

Type: Feature Request

When starting with a Blinky of a device that is not installed, the output in the terminal is

While everything is working as expected, it might be confusing for a first-time user.

[jkrech]

a) For the errors from cpackget running the update-index once a day we need to update the Keil.vidx to remove vendors with failing urls
b) For the "interim" error about the missing toolchain selection, I agree that the terminal only displays the output from cbuild and there is no representation of the CMSIS Solution extension detecting the missing toolchain selection from the *.cbuild-idx.yml, checking for installed compilers and opening a dialog if there is a choice but if there is no selection immediately writing the compiler: in the *.csolution.yml file. Because of the update of a Csolution YAML input file, the cbuild setup is invoked again.

I propose that cbuild setup needs rework to better reflect a status that the IDE is expected to handle instead of "error:", e.g. to_do_ide.