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

calculators/builder-adversary-stateless/run-02/machine-docs/JOURNAL-eval.md

@@ -0,0 +1,34 @@
+# JOURNAL — eval phase
+
+## Implementation run
+
+Ran all checks locally before commit:
+
+```
+$ python -m unittest -q
+----------------------------------------------------------------------
+Ran 45 tests in 0.001s
+OK
+
+$ 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 "1/0"
+error: division by zero
+(exit 1)
+$ python calc.py "1 +"
+error: unexpected end of input
+(exit 1)
+```
+
+All 45 tests pass (20 from parse phase, 14 from lex phase, 11 from evaluator tests).
+
+### Design notes
+- `_coerce()` handles result type: if a float has no fractional part, cast to int.
+- Division by zero caught explicitly and re-raised as `EvalError`.
+- CLI catches `LexError`, `ParseError`, `EvalError` — no raw tracebacks.