This commit turns some stream-based iterations back into simpler
enhanced for loops.
For simple use cases like these, where the stream API is merely used to
map/filter + collect to a List, a for loop is more efficient.
This is especially true for small collections like the ones we deal
with in BodyInserters/BodyExtractors here (in the order of 50ns/op vs
5ns/op). These cases are also simple enough that they don't lose in
readability after the conversion.
Closes gh-30136
800b13492b