Polish: aria-pressed toggles, deferred row styling, override hint

Fund visibility toggles and the header privacy/theme buttons expose
aria-pressed (FE-16); deferred transactions render struck-through and
muted so the state is visible at a glance (UX-05); the balance-override
input documents its keyboard contract (UX-21). The Budget CSV button
rides in the transactions tab header.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

frontend/src/components/budget/YearlyOverview.tsx

@@ -189,6 +189,8 @@ export default function YearlyOverview({
                       onChange={(e) => setEditValue(e.target.value)}
                       onBlur={handleSave}
                       onKeyDown={handleKeyDown}
+                      title="Enter para guardar · vacío para quitar el ajuste · Esc para cancelar"
+                      aria-description="Enter guarda; vacío quita el ajuste"
                       className="h-7 w-36 text-right font-mono text-sm ml-auto"
                       onClick={(e) => e.stopPropagation()}
                     />

frontend/src/components/transactions/transaction-columns.tsx

@@ -107,6 +107,7 @@ export function getTransactionColumns({
             className={cn(
               'font-mono font-medium',
               tx.transaction_type !== 'COMPRA' && 'text-primary',
+              tx.deferred_to_next_cycle && 'opacity-50 line-through decoration-muted-foreground/60',
             )}
           >
             {tx.transaction_type === 'COMPRA' ? '-' : '+'}