v2.0.0 — Major release: ASON 2.0 — formal spec, parser refactor, and tests: - Completed and published the formal ASON specification. - Major refactor of lexer/normalizer/parser pipeline and token model. - Added token-stream reader/writer, error types/printer, and writer utilities. - Breaking changes: public APIs in parsing/lexing AST and token types may be incompatible with previous version.