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

calculators/builder-adversary-deferred/run-03/machine-docs/JOURNAL-lex.md

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+# Journal — lex phase
+
+## Build run
+
+Implemented `calc/lexer.py` with:
+- `Token` dataclass with `kind` (str) and `value` (int | float | str | None)
+- `LexError(Exception)` for invalid characters
+- `tokenize(src: str) -> list[Token]` scanning char-by-char
+
+Design choices:
+- `Token` is a plain dataclass so later phases (parser, evaluator) can pattern-match on `.kind`
+- Numbers: scanned greedily while char is digit or `.`; cast to `int` if no `.` in raw string, else `float`
+- Operators stored as their literal char as `value` (handy for error messages)
+- EOF always appended as final token (parser-friendly sentinel)
+
+## Test run output
+
+```
+$ python -m unittest -q
+..............
+----------------------------------------------------------------------
+Ran 14 tests in 0.000s
+
+OK
+```
+
+## Verify commands output
+
+```
+$ python -c "from calc.lexer import tokenize; print([(t.kind,t.value) for t in tokenize('3.5*(1-2)')])"
+[('NUMBER', 3.5), ('STAR', '*'), ('LPAREN', '('), ('NUMBER', 1), ('MINUS', '-'), ('NUMBER', 2), ('RPAREN', ')'), ('EOF', None)]
+
+$ python -c "from calc.lexer import tokenize; tokenize('1 @ 2')"
+Traceback (most recent call last):
+  ...
+calc.lexer.LexError: unexpected character '@' at position 2
+```