feat(i18n): French and German localization (phase 5)

- Add full message catalogs and content for French (fr) and German (de)
- Implement ASCII canonical slugs for French and German routes
- Add language-specific search endpoints (/api/busca/fr, /api/busca/de)
- Configure strict 404 responses for /fr/livro and /de/livro
- Localize SEO, OpenGraph (fr_FR, de_DE), Twitter and JSON-LD schemas
- Add localized code example comments across 14 examples for fr and de
- Enable 'fr' and 'de' in ENABLED_LOCALES with root negotiation and redirect
- Extend test suite in check-i18n, smoke-imagem and verifica-vazamentos

Co-Authored-By: Antigravity <noreply@google.com>

components/PageHero.jsx

@@ -15,6 +15,8 @@ export default function PageHero({
 	children,
 	isEn: isEnProp,
 	isEs: isEsProp,
+	isFr: isFrProp,
+	isDe: isDeProp,
 	locale: localeProp,
 }) {
 	const center = align === "center";
@@ -30,13 +32,37 @@ export default function PageHero({
 			: localeProp
 			? localeProp === "es"
 			: trail.some((t) => t.isEs || (t.href && t.href.startsWith("/es")));
+	const isFr =
+		isFrProp !== undefined
+			? isFrProp
+			: localeProp
+			? localeProp === "fr"
+			: trail.some((t) => t.isFr || (t.href && t.href.startsWith("/fr")));
+	const isDe =
+		isDeProp !== undefined
+			? isDeProp
+			: localeProp
+			? localeProp === "de"
+			: trail.some((t) => t.isDe || (t.href && t.href.startsWith("/de")));
+
+	const homeHref = isEn ? "/en" : isEs ? "/es" : isFr ? "/fr" : isDe ? "/de" : "/";
+	const homeLabel = isEn ? "Home" : isEs ? "Inicio" : isFr ? "Accueil" : isDe ? "Startseite" : "Início";
+	const breadcrumbAria = isEn
+		? "Breadcrumb navigation"
+		: isEs
+		? "Navegación por migas de pan"
+		: isFr
+		? "Fil d'Ariane"
+		: isDe
+		? "Brotkrumennavigation"
+		: "Trilha de navegação";
 
 	return (
 		<section className="shell pt-8 sm:pt-12">
 			{trail.length > 0 && (
-				<nav aria-label={isEn ? "Breadcrumb navigation" : isEs ? "Navegación por migas de pan" : "Trilha de navegação"} className="flex flex-wrap items-center gap-2 text-sm text-muted">
-					<Link href={isEn ? "/en" : isEs ? "/es" : "/"} className="inline-flex min-h-11 min-w-11 items-center justify-center transition-colors hover:text-accent">
-						{isEn ? "Home" : isEs ? "Inicio" : "Início"}
+				<nav aria-label={breadcrumbAria} className="flex flex-wrap items-center gap-2 text-sm text-muted">
+					<Link href={homeHref} className="inline-flex min-h-11 min-w-11 items-center justify-center transition-colors hover:text-accent">
+						{homeLabel}
 					</Link>
 					{trail.map((item, i) => (
 						<span key={item.label} className="flex min-h-11 items-center gap-2">