Native link/install tasks should report 'no-source' as their outcome when they have no source inputs

These task report either 'up-to-date' or 'skipped' when they have no inputs. This is confusing and inconsistent with the JVM tasks, which instead report 'no-source' as their outcome in this case.

There was a giant discussion in various forums re. this behaviour in JVM land and this discussion came to certain conclusions about how tasks should be behave. I don't want to have that discussion again. We should change the native tasks to honor the outcome of that discussion, ideally in a domain-independent way so that all tasks just do the right thing by default in this situation, and if we think this behaviour should later be refined, we can change it in one place.

Start by locating the native link and install task implementations and the existing JVM handling for tasks with no inputs. Compare their outcomes and trace the shared task behavior to determine whether the change can be made domain-independently; done means native tasks report "no-source" when they have no source inputs and relevant behavior is covered by tests.

Written by the indexing model from the issue text.