Optimize each by manually applying middleware

[robhanlon22]

each already has a reference to the monolith in its context. By manually applying the middleware after inserting its symbol and adding a metadata key that identifies already activated monoliths, the number of project reads and initializations can be reduced.

[greglook]

I wound up reverting this in 1.6.1 because it turned out to break managed dependencies (at least) in the leaky profile. 🤕