Rename app from VaakSiddhi to Vaakify (visible branding only — backend URLs unchanged)

Complete dark mode rollout, add real logo (centered), fix duplicate flag icons, improve dark gradient contrast

Override phoneme scoring with dedicated confusable-check model, new BOLT starfield backdrop, logo-inspired gradient for unselected states

Fix hook-order crash in AIAssistant, add background cleanup on LanguageSelect unmount

fix React error 310 - move body style to useEffect

add multilingual support: language select, i18n, word suggestions, Kannada phonemes, translate endpoint