Map collection and fields for `$lookup`/`$graphLookup` aggregation stage against domain type

[christophstrobl]

This commit enables using a type parameter to define the from collection of a $lookup/$graphLookup aggregation stage. In doing so we can derive the target collection name from the type and use the given information to also map the from field against the domain object to so that the user is able to operate on property names instead of the target document field name.

Resolves: #4379