style(ui): polimento visual — tema, cards, dark mode e landing page

Raio de borda global 0.625rem → 0.7rem; ajustes finos em --card e --border.
DotPattern removido do layout, tela de auth e landing page.
Account-card redesenhado (cores de saldo, tooltip de flags de exclusão).
Budget-card, card-item, calendário (day-cell, event-modal) com layout revisado.
Auth-card-shell simplificado (sem glassmorphism/blob). Landing page com
mainFeatures + extraFeatures em grid único e dark mode nos botões de CTA.
Imagens de preview da landing atualizadas. CSS --data-7..10 removidas.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/shared/components/logo-picker/logo-picker.tsx

@@ -59,7 +59,7 @@ export function LogoPickerTrigger({
 						className="object-contain p-0.5"
 					/>
 				) : (
-					<span className="text-[10px] text-muted-foreground">Logo</span>
+					<span className="text-xs text-muted-foreground">Logo</span>
 				)}
 			</span>
 
@@ -172,7 +172,7 @@ export function LogoPickerDialog({
 											/>
 										</span>
 									</span>
-									<span className="line-clamp-1 text-[10px] leading-tight text-muted-foreground">
+									<span className="line-clamp-1 text-xs leading-tight text-muted-foreground">
 										{logoLabel}
 									</span>
 								</button>