Qute: support TemplateRoot outside of src/main/resources

[ia3andy]

AFAIK it's currently not possible?

Use case is Quarkus Roq

[quarkus-bot[bot]]

/cc @mkouba (qute)

[mkouba]

A template root is always relative to an application artifact, or the root dir. It cannot be an arbitrary directory because the scanning logic must work in all run modes (production, dev mode, tests, etc.). If you look at the implementation we basically scan all archives from the ApplicationArchivesBuildItem.