Many features were documented as "missing" or "planned" but are actually
working: generics, string interpolation, File/HTTP/Random/Time effects,
JSON parsing, module system, and JIT CLI integration.
Updated IMPLEMENTATION_PLAN.md, OVERVIEW.md with accurate status.
Added ROADMAP.md (use-case-targeted) and LANGUAGE_COMPARISON.md.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
