Support packaging hst repository configuration with either repository or site application

The hst-addon-repository module provides the hst repository configuration (hcm-module) for both 'global' repository/bootstrap configuration as well as default /hst:hst root configurations.

With the new Multi-Site feature the /hst:hst root configurations by default now must be bundled and packaged with the site web application.

Therefore a new module (jar artifact) hst-addon-hcm-hst will be created which separates out the /hst:hst root repository configuration.

Additionally, it was discovered that already long time ago (HSTTWO-3500) the hippo-addon-search-service modules were added as dependencies to the hst-restapi module (and as result packaged in the hst site war). This however now causes a problem because it also is providing backend/repository level services with related cnd and bootstrap configuration which only should be packaged with the repository.
Somehow this needs to be decoupled but this is non-trivial as both use-cases are overlapping in API usages... To be determined still how to solve this.