InjectionToken can be created with an ngInjectableDef, and previously
this allowed the full expressiveness of @Injectable. However, this
requires a runtime reflection system in order to generate factories
from expressed provider declarations.
Instead, this change requires scoped InjectionTokens to provide the
factory directly (likely using inject() for the arguments), bypassing
the need for a reflection system.
Fixes#22205
PR Close#22207