Is your feature request related to a problem? Please describe.

Is your feature request related to a problem?

Not really. just following the maintainer guides to prefer CMake over all else. and the current b2 hacks vcpkg uses generate problems. CMake is easier to maintain from a vcpkg perspective since more people know how to use it correctly.

Proposed solution

Currently boost only provides a monolithic build system which is either b2 or cmake. vcpkg currently hacks something together with b2 rules. I propose to hack something together with CMake instead since boost will then provide cmake config files which are better and easier to consume then using cmakes FindBoost.
The main problems:

• cmake build is monolithic, superporject build
• sublibs have no install rules
• sublibs do not generate a config
• sublibs do not have find_package calls.

However:

• sublibs follow easy to predict pattern for include and target names
• we have cmake to inject whenever and whatever we need
• BoostConfig.cmake already does a component vise lookup https://github.com/boostorg/cmake/blob/69f16e2819c4686450bdac807e3eb58346fb2ac2/config/BoostConfig.cmake#L67
• Boost already has a lot of useful functions in https://github.com/boostorg/cmake/blob/69f16e2819c4686450bdac807e3eb58346fb2ac2/include/BoostInstall.cmake and https://github.com/boostorg/cmake/blob/69f16e2819c4686450bdac807e3eb58346fb2ac2/include/BoostRoot.cmake which probably just need a little patching to make it work modular.

As such vcpkg should probably switch to using CMake for boost in the future.

Describe alternatives you've considered

Stay with b2 and fight stuff like #27694 (not really and option ;))

Additional context

No response

### Tasks
- [ ] https://github.com/microsoft/vcpkg/pull/32309