Dependency model

BESA separates why a dependency exists from how CMake discovers it.

KIND is one of NORMAL, BUILD, or DEV. Normal dependencies belong to the product and are written into generated consumer package metadata. Build dependencies are needed to construct the software but not to consume it. Dev dependencies belong to testing, documentation, analysis, or other development workflows and are never propagated to consumers.

PROVIDER currently distinguishes CMAKE from PKGCONFIG. The CMake provider deliberately relies on find_package() rather than requiring a particular metadata format. Consequently a dependency can move from a traditional CMake package config toward CPS when the active CMake/dependency supports it without changing the BESA project declaration.

This information is intentionally richer than a raw find_package() call because it is also the foundation for a future package/build model in which normal, build, and dev dependency graphs can be handled differently.