cl: Phase 2 eval — 127 tests, 299 total green

lib/common-lisp/eval.sx: cl-eval-ast implementing quote, if, progn,
let/let*, flet, labels, setq/setf, function, lambda, the, locally,
eval-when, defun, defvar/defparameter/defconstant, built-in arithmetic
(+/-/*//, min/max/abs/evenp/oddp), comparisons, predicates, list ops,
string ops, funcall/apply/mapcar.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/common-lisp/tests/lambda.sx

@@ -97,7 +97,7 @@
 (cl-test
   "optional: string default"
   (ll-opt "(&optional (name \"world\"))")
-  (list {:name "NAME" :default "world" :supplied nil}))
+  (list {:name "NAME" :default {:cl-type "string" :value "world"} :supplied nil}))
 
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