Modern bottom navigation bar for mobile with MEMES, CODE, WALLETS
and LANG dropup. Always visible, no hamburger toggle needed.
Matches the gradient style of the top navbar.
Add LANG dropdown to desktop and mobile navbars with all available
translations. Use localStorage to persist language choice across
page loads. Fix undefined key errors in traduction.js. Handle
English selection by clearing stored preference and reloading.
Rename pt_BR.json to pt-BR.json to match navigator.language format.
Fix spelling issues (compravado->comprovado, monstre->mostre, commando->comando,
crecendo->crescendo, etc). Fill in all missing translation keys for current
index.html IDs. Add pt-PT.json copy. Add "pt" language mapping in traduction.js.
jwinterm