Be smarter with when to wrap in IIFE

[planttheidea]

Reason for change

The original setup was an introspection of both contents and ancestral tree, which led to wrapping things in IIFEs when not necessary. Because there is a (tiny, but present) cost to IIFEs vs pure inline logic, more intelligence is warranted.

Change

Modify shouldWrapInClosure to focus exclusively on the callsite's scope. This involves:

• Recursion to verify ancestral tree to bail out on first wrap case, to better handle usage in a nested expression scenario
• Checking the body size of the function parent to determine if there are any other operations within the scope