split bundle config into tauri.{windows,linux,macos}.conf.json so each
platform only carries its own targets; gen-icon emits icon.icns; macos is
ad-hoc signed since arm64 refuses unsigned downloads
replaces new Function() in the main window; per-script and per-call
interrupt deadlines, memory and stack limits, graceful skip if the
wasm module fails to load. csp script-src drops 'unsafe-eval' for
'wasm-unsafe-eval'.