Vite defaulted to an IPv6-only bind, so tauri dev's readiness probe
(which checks 127.0.0.1) waited forever even though Vite was up.
Separately, its file watcher was watching Rust's build output and
crashed on a locked .pdb file mid-compile.
Write plain text, get live results per line. English + Russian, units,
live currency rates with crypto, percents, dates and timezones, bitwise
ops, variables and sheet totals. Tauri 2 + TypeScript engine +
CodeMirror 6; daily backups and a deleted-sheets bin.
Inspired by Numi for macOS (numi.app); built from scratch for Windows.