Framework-free helper utilities. Pure where possible; no DOM-dependent globals.
helpers.js—debounce,throttle,generateId,getNestedValue,deepMerge,isObject,escapeHTML,formatDate,parseQueryParams,createElement,requestIdleCallback,loadScript/loadCSS,getDeviceInfo,getElementSelector,isInViewport,smoothScrollTo. Fully unit-tested (tests/unit/helpers.test.js).storage.js—LocalStorage/SessionStoragesafe wrappers with an in-memory fallback whenlocalStorage/sessionStorageis unavailable. Tested (tests/unit/storage.test.js), including the fallback branch.
Layer: depends only on config.