fix: parse hyphenated strings correctly inside container literals

[Yadidiah-k]

Fixes #561

What was wrong

When a hyphenated string like foo-bar appears inside a container literal — tuple, list, set, or dict — Python's ast.parse turns the hyphen into a BinOp(Sub) node (foo - bar). The AST walker in _LiteralEval only replaced bare Name nodes with strings; it left BinOp nodes untouched. When ast.literal_eval then encountered the unresolved BinOp, it raised ValueError, and the entire container fell back to a plain string.

# Before
>>> fire.Fire(lambda obj: type(obj).__name__, '(foo-bar,baz)')
str        # should be tuple

# After  
>>> fire.Fire(lambda obj: type(obj).__name__, '(foo-bar,baz)')
tuple

Fix

Added _BinOpSubToStr, a helper that recursively converts a Name-Sub-Name chain back to a hyphenated string (handles multi-segment names like a-b-c too). The walker now calls it alongside _Replacement for both list children and single-value fields. Works for tuples, lists, and dicts.

Numeric subtraction like 123-456 is unaffected — Constant nodes are not Name nodes and _BinOpSubToStr returns None for them, so no replacement happens.

Tests added

• testDefaultParseValueHyphenatedStringsInTuple
• testDefaultParseValueHyphenatedStringsInList
• testDefaultParseValueHyphenatedStringsInDict

All 23 parser tests pass.

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