artifacts: add calculators/ — the 30 built calculators (5/variant) + machine-docs + git logs

calculators/builder-adversary-lean/run-05/machine-docs/JOURNAL-eval.md

@@ -0,0 +1,35 @@
+# JOURNAL — eval phase
+
+## Session 1
+
+Implemented evaluator, CLI, and tests in one pass.
+
+### evaluator.py design
+
+`evaluate(node)` recursively walks `Num`, `BinOp`, `Unary` nodes. `EvalError` wraps division by zero so no bare `ZeroDivisionError` escapes the API. `_normalize(value)` converts whole-valued floats to int (satisfying D3).
+
+### Test run
+
+```
+$ python -m unittest -q
+Ran 69 tests in 0.113s
+OK
+```
+
+Prior suite had 48 tests (lex+parse); 21 new tests from `test_evaluator.py`.
+
+### CLI manual check
+
+```
+$ python calc.py "2+3*4"   → 14
+$ python calc.py "(2+3)*4" → 20
+$ python calc.py "7/2"     → 3.5
+$ python calc.py "4/2"     → 2
+$ python calc.py "8-3-2"   → 3
+$ python calc.py "-2+5"    → 3
+$ python calc.py "2*-3"    → -6
+$ python calc.py "1/0"     → error: division by zero (exit 1)
+$ python calc.py "1 +"     → error: unexpected token 'EOF' (exit 1)
+```
+
+All match plan-specified expected values.