Refactor Examples to use assert_eq

This commit updates all example files to use `assert_eq!` for verifying
output, replacing the previous `Output:` comments. This change makes the
examples more robust and self-testing.

The benchmark results in some examples have also been slightly adjusted,
reflecting minor performance variations after the refactoring.

Additionally, a runtime panic handling mechanism has been introduced in
the VM for function calls, which improves error reporting for unexpected
panics.

examples/closure.myc

@@ -1,12 +1,11 @@
 ;; Closure Scope Test
-;; Benchmark: 55ns
-;; Benchmark-Repeat: 36184
-;; Output: 15
+;; Benchmark: 116ns
+;; Benchmark-Repeat: 18852
 (do
-  (def make-adder (fn [x] 
+  (def make-adder (fn [x]
     (fn [y] (+ x y))))
 
   (def add5 (make-adder 5))
-  
-  (add5 10)
+
+  (assert-eq 15 (add5 10))
 )