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/components/pagefind-highlighter.tsx

@@ -0,0 +1,54 @@
+"use client"
+
+import { useEffect } from "react"
+import { usePathname, useSearchParams } from "next/navigation"
+
+declare global {
+  interface Window {
+    PagefindHighlight?: new (options: { highlightParam?: string; addStyles?: boolean }) => unknown
+  }
+}
+
+/*
+  Pagefind term highlighter.
+
+  pagefind-highlight.js only attaches the `PagefindHighlight` class to window — it does
+  NOT auto-run. We instantiate it here on every route change so that:
+    1. Initial page load: runs after the script loads.
+    2. SPA navigation from search results (router.push from search-dialog.tsx): re-runs
+       so highlights apply on the new page even though the page wasn't fully reloaded.
+
+  We pass `highlightParam: "pagefind-search"` to match what the search dialog appends.
+*/
+export function PagefindHighlighter() {
+  const pathname = usePathname()
+  const searchParams = useSearchParams()
+
+  useEffect(() => {
+    if (!searchParams?.get("pagefind-search")) return
+
+    const run = () => {
+      if (typeof window.PagefindHighlight !== "function") return false
+      try {
+        new window.PagefindHighlight({ highlightParam: "pagefind-search" })
+      } catch {
+        // Highlighter constructor throws if mark.js can't find any text nodes — harmless.
+      }
+      return true
+    }
+
+    if (run()) return
+
+    // Script may not have loaded yet on first paint; poll briefly.
+    const id = window.setInterval(() => {
+      if (run()) window.clearInterval(id)
+    }, 100)
+    const timeout = window.setTimeout(() => window.clearInterval(id), 5000)
+    return () => {
+      window.clearInterval(id)
+      window.clearTimeout(timeout)
+    }
+  }, [pathname, searchParams])
+
+  return null
+}