[Nigh]

Summary

• replace dynamic expression execution with a source-aware tokenizer, typed AST, Pratt parser, and controlled interpreter
• add arbitrary-precision integers, Decimal and Rational arithmetic, user functions, lambdas, ranges, destructuring, vectorized arrays, and matrices
• add engineering utilities for bit operations, number theory, Hamming SECDED, strict encodings, color spaces, statistics, crypto random values, and numerical root solving
• migrate the editor to CodeMirror with resilient highlighting, structured errors, active/hover result linking, and pixel-aligned multi-line matrix output
• add persistent per-line numeric and color result formatting, improved PWA behavior, accessibility, automated unit/e2e verification, and CI

Validation

• 63 Vitest tests passed
• 6 Playwright tests passed
• Astro/TypeScript check completed with 0 errors
• production build passed

Notes

• function definitions now use fn instead of def
• the expression language is intentionally controlled and does not expose browser globals
• // is a whole-line comment marker only at the start of a trimmed line; inside expressions it is integer division