Using the opportunity of our API for buffer getters in the RTC program output changing from the not-really-dynarray to a span, let's also make sure all of the actual-text-strings there are put in buffers with a trailing '\0'. This is not strictly necessary, as a span is not guaranteed to also work as a C-style, nul-terminated string - but it's safer if we do that, in case someone mishandles the returned container and treats its data like that.
Using the opportunity of our API for buffer getters in the RTC program output changing from the not-really-dynarray to a span, let's also make sure all of the actual-text-strings there are put in buffers with a trailing '\0'. This is not strictly necessary, as a span is not guaranteed to also work as a C-style, nul-terminated string - but it's safer if we do that, in case someone mishandles the returned container and treats its data like that.