TermSanitizer

Sanitizes UPLC Terms to ensure all variable names conform to the identifier grammar accepted by the reference plutus-core textual parser (PlutusCore.Parser.ParserCommon.name, backed by PlutusCore.Name.Unique.isIdentifierStartingChar / isIdentifierChar; verified against plutus-core-1.45.0.0):

• First character: an ASCII letter (a-z, A-Z) or underscore (_).
• Subsequent characters: an ASCII letter, digit, underscore (_), or apostrophe (').
• The reference parser additionally accepts a - "Unique" suffix (e.g. foo-123), but only as a terminal token component parsed by a separate combinator: once - starts, nothing else (not even more digits, letters, or apostrophes) may follow it in the same token. A name like a-91533'653 therefore parses as a-91533 followed by a stray, unparseable '653. Since Scalus never needs to emit that literal Unique-suffix syntax, this sanitizer does not attempt to reproduce it: every - in an original name is replaced with _ instead, which is always valid in any position and sidesteps the terminal-suffix ambiguity entirely.

This sanitizer transforms variable names to comply with these rules while avoiding conflicts.