Group scons targets better (#18885)
Fixup of #18880
Summary of the issue:
#18880 broke signed builds, as building the controller client requires signing, and #18880 tried to build the controller client without signpath installed.
It also failed to fix #18867 properly, as the full user_docs was not built until scons launcher was called
Description of user facing changes:
None
Description of developer facing changes:
Fixed #18880 properly
Description of development approach:
Build all docs in a grouped job
Build client & launcher in a separate job
