feat(i18n): English localization (phase 3)

- Translate content to English across messages/en.json, data/en, lib/data/en, and public/exemplos/en
- Implement localized routing, slugs, and language negotiation with fallback to en
- Build dedicated search index for English with strict book exclusion
- Update components and pages to dynamically render localized strings and datasets
- Verify full structural parity and exact 1:1 match on Portuguese pages via comparator

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

components/Footer.jsx

@@ -8,7 +8,7 @@ import { ArrowUpRight } from "lucide-react";
 import { SITE } from "@/lib/seo";
 import { LOCALES, getLocalizedHref } from "@/i18n/links";
 
-const COLUMNS = [
+const COLUMNS_PT = [
 	{
 		title: "Explorar",
 		links: [
@@ -38,6 +38,35 @@ const COLUMNS = [
 	},
 ];
 
+const COLUMNS_EN = [
+	{
+		title: "Explore",
+		links: [
+			{ href: "/series", label: "ESP32 Series" },
+			{ href: "/comparacao", label: "Comparator" },
+			{ href: "/catalogo", label: "Board Catalog" },
+		],
+	},
+	{
+		title: "Tools",
+		links: [
+			{ href: "/seletor", label: "Smart Selector" },
+			{ href: "/diagnostico", label: "Diagnostics" },
+			{ href: "/componentes", label: "Component Registry" },
+			{ href: "/frameworks", label: "Frameworks & SDKs" },
+		],
+	},
+	{
+		title: "Project",
+		links: [
+			{ href: "/sobre", label: "About ESPDocs" },
+			{ href: "/glossario", label: "Glossary" },
+			{ href: SITE.repositorio, label: "Repository", external: true },
+			{ href: `${SITE.repositorio}/issues`, label: "Report an issue", external: true },
+		],
+	},
+];
+
 export default function Footer() {
 	const pathname = usePathname() || "";
 	const year = new Date().getFullYear();
@@ -48,23 +77,34 @@ export default function Footer() {
 
 	const getLinkHref = (href) => getLocalizedHref(`/${currentLocale}${href}`, currentLocale);
 
-	const columns = COLUMNS.map((column) => ({
-		...column,
-		links: column.links.filter((link) => link.href !== "/livro" || isPt),
-	}));
+	const columns = isPt
+		? COLUMNS_PT.map((column) => ({
+				...column,
+				links: column.links.filter((link) => link.href !== "/livro" || isPt),
+		  }))
+		: COLUMNS_EN;
 
 	return (
-		<footer className="mt-20 border-t border-line md:mt-28" aria-label="Rodapé do ESPDocs">
+		<footer className="mt-20 border-t border-line md:mt-28" aria-label={isPt ? "Rodapé do ESPDocs" : "ESPDocs footer"}>
 			<div className="shell py-14 md:py-20">
 				<div className="grid gap-12 lg:grid-cols-[1.1fr_2fr]">
 					<div>
-						<Link href={getLinkHref("/")} className="inline-flex min-h-11 items-center gap-2.5" aria-label="ESPDocs, página inicial">
+						<Link href={getLinkHref("/")} className="inline-flex min-h-11 items-center gap-2.5" aria-label={isPt ? "ESPDocs, página inicial" : "ESPDocs, homepage"}>
 							<Logo className="h-7 w-7" />
 							<span className="font-display text-2xl font-semibold tracking-[-0.045em] text-ink">ESPDocs</span>
 						</Link>
 						<p className="mt-5 max-w-sm text-sm leading-relaxed text-muted">
-							Documentação independente do ecossistema ESP32, escrita em português brasileiro.
-							Dados públicos, curadoria editorial e links para as fontes oficiais.
+							{isPt ? (
+								<>
+									Documentação independente do ecossistema ESP32, escrita em português brasileiro.
+									Dados públicos, curadoria editorial e links para as fontes oficiais.
+								</>
+							) : (
+								<>
+									Independent documentation of the ESP32 ecosystem.
+									Open data, editorial curation, and links to official sources.
+								</>
+							)}
 						</p>
 
 						{isPt && (
@@ -133,7 +173,7 @@ export default function Footer() {
 						))}
 
 						<div>
-							<h2 className="text-sm font-semibold text-ink">Autor</h2>
+							<h2 className="text-sm font-semibold text-ink">{isPt ? "Autor" : "Author"}</h2>
 							<p className="mt-4 text-sm leading-relaxed text-muted">
 								Lucas Rayan Guerra
 								<br />
@@ -144,7 +184,7 @@ export default function Footer() {
 									href={SITE.repositorio}
 									target="_blank"
 									rel="noopener noreferrer"
-									aria-label="Gitea do projeto (abre em nova aba)"
+									aria-label={isPt ? "Gitea do projeto (abre em nova aba)" : "Project Gitea (opens in new tab)"}
 									className="grid h-11 w-11 place-items-center rounded-full border border-line text-ink transition-colors hover:border-line-strong hover:bg-surface"
 								>
 									<GiteaMark className="h-4 w-4" />
@@ -153,7 +193,7 @@ export default function Footer() {
 									href={SITE.autorLinkedin}
 									target="_blank"
 									rel="noopener noreferrer"
-									aria-label="LinkedIn do autor (abre em nova aba)"
+									aria-label={isPt ? "LinkedIn do autor (abre em nova aba)" : "Author LinkedIn (opens in new tab)"}
 									className="grid h-11 w-11 place-items-center rounded-full border border-line text-ink transition-colors hover:border-line-strong hover:bg-surface"
 								>
 									<svg className="h-4 w-4" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true">
@@ -166,7 +206,7 @@ export default function Footer() {
 				</div>
 
 				<div className="mt-14 flex flex-col gap-4 border-t border-line pt-6 text-xs leading-relaxed text-faint md:flex-row md:items-center md:justify-between">
-					<p>© {year} ESPDocs. Projeto independente, sem afiliação com a Espressif Systems.</p>
+					<p>© {year} {isPt ? "ESPDocs. Projeto independente, sem afiliação com a Espressif Systems." : "ESPDocs. Independent project, not affiliated with Espressif Systems."}</p>
 					<p className="flex flex-wrap items-center gap-x-5 gap-y-2">
 						<a href={SITE.blog} target="_blank" rel="noopener noreferrer" className="inline-flex min-h-11 items-center gap-1 transition-colors hover:text-accent">
 							Ciência Embarcada
@@ -176,7 +216,7 @@ export default function Footer() {
 							lucasrguerra.dev.br
 							<ArrowUpRight className="h-3 w-3" aria-hidden="true" />
 						</a>
-						<span>Fontes oficiais: Espressif Systems.</span>
+						<span>{isPt ? "Fontes oficiais: Espressif Systems." : "Official sources: Espressif Systems."}</span>
 					</p>
 				</div>
 			</div>