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>

plans/common-lisp-on-sx.md

@@ -56,14 +56,14 @@ Core mapping:
 - [x] Unit tests in `lib/common-lisp/tests/read.sx`
 
 ### Phase 2 — sequential eval + special forms
-- [ ] `cl-eval-ast`: `quote`, `if`, `progn`, `let`, `let*`, `flet`, `labels`, `setq`, `setf` (subset), `function`, `lambda`, `the`, `locally`, `eval-when`
+- [x] `cl-eval-ast`: `quote`, `if`, `progn`, `let`, `let*`, `flet`, `labels`, `setq`, `setf` (subset), `function`, `lambda`, `the`, `locally`, `eval-when`
 - [ ] `block` + `return-from` via captured continuation
 - [ ] `tagbody` + `go` via per-tag continuations
 - [ ] `unwind-protect` cleanup frame
 - [ ] `multiple-value-bind`, `multiple-value-call`, `multiple-value-prog1`, `values`, `nth-value`
-- [ ] `defun`, `defparameter`, `defvar`, `defconstant`, `declaim`, `proclaim` (no-op)
+- [x] `defun`, `defparameter`, `defvar`, `defconstant`, `declaim`, `proclaim` (no-op)
 - [ ] Dynamic variables — `defvar`/`defparameter` produce specials; `let` rebinds via parameterize-style scope
-- [ ] 60+ tests in `lib/common-lisp/tests/eval.sx`
+- [x] 127 tests in `lib/common-lisp/tests/eval.sx`
 
 ### Phase 3 — conditions + restarts (THE SHOWCASE)
 - [ ] `define-condition` — class hierarchy rooted at `condition`/`error`/`warning`/`simple-error`/`simple-warning`/`type-error`/`arithmetic-error`/`division-by-zero`
@@ -114,6 +114,7 @@ Core mapping:
 
 _Newest first._
 
+- 2026-04-25: Phase 2 eval — 127 tests, 299 total green. `lib/common-lisp/eval.sx`: cl-eval-ast with 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 (car/cdr/cons/list/append/reverse/length/nth/first/second/third/rest), string ops, funcall/apply/mapcar. Key gotchas: SX reduce is (reduce fn init list) not (reduce fn list init); CL true literal is t not true; builtins registered in cl-global-env.fns via wrapper dicts for #' syntax.
 - 2026-04-25: Phase 1 lambda-list parser — 31 new tests, 172 total green. `cl-parse-lambda-list` in `parser.sx` + `tests/lambda.sx`. Handles &optional/&rest/&body/&key/&aux/&allow-other-keys, defaults, supplied-p. Key gotchas: `(when (> (len items) 0) ...)` not `(when items ...)` (empty list is truthy); custom `cl-deep=` needed for dict/list structural equality in tests.
 - 2026-04-25: Phase 1 reader/parser — 62 new tests, 141 total green. `lib/common-lisp/parser.sx`: cl-read/cl-read-all, lists, dotted pairs, quote/backquote/unquote/splice/#', vectors, #:uninterned, NIL→nil, T→true, reader macro wrappers.
 - 2026-04-25: Phase 1 tokenizer — 79 tests green. `lib/common-lisp/reader.sx` + `tests/read.sx` + `test.sh`. Handles symbols (pkg:sym, pkg::sym), integers, floats, ratios, hex/binary/octal, strings, #\ chars, reader macros (#' #( #: ,@), line/block comments. Key gotcha: SX `str` for string concat (not `concat`), substring-based read-while.