Tools should not be in the default metadata gathering

When you depend on a tool it should not be included in the license/metadata gathering.
We have the filtering function, but it is insufficient.

Some ideas:
- filter any dependency in the exec configuration. Crude but mostly right.
- metadata about the attribute usage on attributes. Elegant but hard.

Start with the existing filtering function and inspect how default license/metadata gathering handles dependencies from the exec configuration. Compare that behavior with attribute usage metadata, using the issue's two proposed approaches as the scope. Done means tool dependencies are excluded from default license/metadata gathering without filtering ordinary dependencies.

Written by the indexing model from the issue text.