complete i18n migration to /[locale]/ with EN+ES content

Full rewrite of the docs site under app/[locale]/ with next-intl
in localePrefix:"always" mode. Every page now exists at both
/en/<path> and /es/<path>; the root / shows a meta-refresh + JS
redirect to /<defaultLocale>/ so GitHub Pages serves something
on the apex URL.

Highlights:
- 107 doc pages migrated to file-per-page JSON namespaces under
  messages/en/ and messages/es/. Spanish content is fully
  translated (no copy-of-English placeholders).
- New documentation for the Active Suppressions section in the
  Settings tab and the per-event Dismiss dropdown in the Health
  Monitor modal.
- New screenshots: dismiss-duration-dropdown.png and an updated
  health-suppression-settings.png.
- Pagefind integrated for client-side search; index is built on
  every CI deploy (not committed).
- RSS feeds: per-locale at /<locale>/rss.xml plus root /rss.xml
  for backward compat.
- Removed the dead app/[locale]/guides/[slug]/ route — every
  guide now has its own static page and no markdown source
  remains.
- Fixed orphan link /guides/nvidia -> /guides/nvidia-manual in
  docs/hardware/nvidia-host.
- Removed obsolete components (footer2, calendar, drawer).

Verified locally with `npm ci && npm run build`: 2804 files in
out/, 231 pages indexed by pagefind, root redirect intact, both
locale roots and the new Active Suppressions docs render OK.

web/app/sitemap.ts

@@ -0,0 +1,42 @@
+import type { MetadataRoute } from "next"
+import fs from "fs"
+import path from "path"
+
+export const dynamic = "force-static"
+
+const SITE_URL = "https://proxmenux.com"
+
+function walkDocsRoutes(dir: string, baseRoute: string): string[] {
+  const routes: string[] = []
+  if (!fs.existsSync(dir)) return routes
+
+  const entries = fs.readdirSync(dir, { withFileTypes: true })
+
+  for (const entry of entries) {
+    const full = path.join(dir, entry.name)
+    if (entry.isDirectory()) {
+      routes.push(...walkDocsRoutes(full, `${baseRoute}/${entry.name}`))
+    } else if (entry.name === "page.tsx" || entry.name === "page.mdx") {
+      routes.push(baseRoute || "/")
+    }
+  }
+
+  return routes
+}
+
+export default function sitemap(): MetadataRoute.Sitemap {
+  const appDir = path.join(process.cwd(), "app")
+  const discovered = walkDocsRoutes(appDir, "")
+    .filter((r) => !r.includes("/api/"))
+    .map((r) => (r === "" ? "/" : r))
+
+  const unique = Array.from(new Set(discovered))
+  const now = new Date()
+
+  return unique.map((route) => ({
+    url: `${SITE_URL}${route}`,
+    lastModified: now,
+    changeFrequency: route.startsWith("/docs") ? "weekly" : "monthly",
+    priority: route === "/" ? 1.0 : route.startsWith("/docs") ? 0.8 : 0.6,
+  }))
+}