feat: Implement closure cracking and inlining

Introduces a new optimizer pass that can "crack" closures, allowing for
more aggressive specialization. It also enables inlining of upvalues
that point to immutable global variables. This removes overhead for
higher-order functions and currying when arguments are statically
resolvable.

examples/closure_cracking_named.myc

@@ -0,0 +1,5 @@
+;; Output: 5
+(do
+    (def f (fn [x] (fn [] x)))
+    ((f 5))
+)