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/DocTableOfContents.tsx

@@ -0,0 +1,131 @@
+"use client"
+
+import { useEffect, useState } from "react"
+import { usePathname } from "next/navigation"
+import { useTranslations } from "next-intl"
+
+type Heading = { id: string; text: string; level: 2 | 3 }
+
+/**
+ * Right-rail table of contents for docs pages.
+ *
+ * On mount it walks every <h2> and <h3> inside `<main>` (the docs
+ * container), assigns each one an `id` derived from its text if it
+ * doesn't already have one, and renders a sticky list of anchors.
+ *
+ * Why client-side and not server-rendered? Most docs pages emit
+ * headings as plain JSX without ids — extracting them at build time
+ * would require either touching all ~107 pages or a custom MDX
+ * pipeline. A 15-line useEffect avoids both.
+ *
+ * Scroll-spy: an IntersectionObserver highlights the entry whose
+ * heading is currently in the upper half of the viewport, so the user
+ * can see where they are as they scroll.
+ *
+ * Only renders on xl+ screens (the layout reserves the right gutter
+ * there); on smaller viewports the ToC stays hidden so the article
+ * keeps full width.
+ */
+export function DocTableOfContents() {
+  const pathname = usePathname()
+  const t = useTranslations("tocPanel")
+  const [headings, setHeadings] = useState<Heading[]>([])
+  const [activeId, setActiveId] = useState<string>("")
+
+  // Re-scan whenever the route changes (so navigating between docs
+  // pages refreshes the ToC).
+  useEffect(() => {
+    const main = document.querySelector("main")
+    if (!main) {
+      setHeadings([])
+      return
+    }
+    const nodes = Array.from(main.querySelectorAll("h2, h3")) as HTMLHeadingElement[]
+    const used = new Set<string>()
+    const collected: Heading[] = nodes
+      .map((node) => {
+        const text = (node.textContent || "").trim()
+        if (!text) return null
+        // Always dedupe: if a heading carries an explicit id that already
+        // appeared (e.g. a card <h3>VM</h3> auto-slugged to "vm" before a
+        // <h2 id="vm"> later in the page), append -2, -3, ... so React
+        // keys stay unique. The scroll-anchor still works for the first
+        // occurrence; subsequent ones get their own anchor.
+        let base = node.id || slugify(text)
+        let id = base
+        let n = 1
+        while (used.has(id)) {
+          n += 1
+          id = `${base}-${n}`
+        }
+        if (!node.id || node.id !== id) {
+          node.id = id
+        }
+        used.add(id)
+        return { id, text, level: node.tagName === "H3" ? 3 : 2 } as Heading
+      })
+      .filter((h): h is Heading => h !== null)
+    setHeadings(collected)
+  }, [pathname])
+
+  // Scroll-spy: highlight the heading currently in the upper half of
+  // the viewport. Using rootMargin pushes the trigger zone toward the
+  // top so the active entry changes as you scroll, not only when the
+  // heading is dead-centre.
+  useEffect(() => {
+    if (headings.length === 0) return
+    const observer = new IntersectionObserver(
+      (entries) => {
+        const visible = entries.filter((e) => e.isIntersecting)
+        if (visible.length > 0) {
+          // First visible entry from the top of the viewport.
+          visible.sort((a, b) => a.boundingClientRect.top - b.boundingClientRect.top)
+          setActiveId(visible[0].target.id)
+        }
+      },
+      { rootMargin: "-80px 0px -70% 0px", threshold: 0 },
+    )
+    headings.forEach((h) => {
+      const el = document.getElementById(h.id)
+      if (el) observer.observe(el)
+    })
+    return () => observer.disconnect()
+  }, [headings])
+
+  if (headings.length === 0) return null
+
+  return (
+    <nav
+      aria-label={t("onThisPage")}
+      className="text-sm sticky top-20 max-h-[calc(100vh-6rem)] overflow-y-auto pl-4"
+    >
+      <p className="font-semibold text-gray-900 mb-3 uppercase tracking-wide text-xs">{t("onThisPage")}</p>
+      <ul className="space-y-1.5 border-l border-gray-200">
+        {headings.map((h) => (
+          <li key={h.id} className={h.level === 3 ? "ml-3" : ""}>
+            <a
+              href={`#${h.id}`}
+              className={`-ml-px block border-l-2 pl-3 py-0.5 transition-colors ${
+                activeId === h.id
+                  ? "border-blue-500 text-blue-600 font-medium"
+                  : "border-transparent text-gray-600 hover:text-gray-900 hover:border-gray-300"
+              }`}
+            >
+              {h.text}
+            </a>
+          </li>
+        ))}
+      </ul>
+    </nav>
+  )
+}
+
+function slugify(text: string): string {
+  return text
+    .toLowerCase()
+    .normalize("NFD")
+    .replace(/[̀-ͯ]/g, "")
+    .replace(/[^a-z0-9]+/g, "-")
+    .replace(/(^-|-$)/g, "")
+    .slice(0, 80)
+}