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/ui/doc-navigation.tsx

@@ -1,40 +1,96 @@
 "use client"
 
-import Link from "next/link"
+// Use the locale-aware Link + usePathname from next-intl. With the
+// plain `next/link` and `next/navigation` imports the hrefs were
+// emitted without a locale (404s) AND the active-page detection
+// failed because `pathname` carried the `/en/` prefix while sidebar
+// items don't, so findIndex always returned -1 → no Previous/Next
+// buttons. See app/[locale]/docs/layout.tsx for the wider context.
+import { Link, usePathname } from "@/i18n/navigation"
 import { ChevronLeft, ChevronRight } from "lucide-react"
-import { usePathname } from "next/navigation"
+import { useTranslations } from "next-intl"
 import { sidebarItems } from "@/components/DocSidebar"
 
 interface DocNavigationProps {
   className?: string
 }
 
+interface SubMenuItem {
+  title: string
+  i18nKey?: string
+  href: string
+  submenu?: SubMenuItem[]
+}
+
+interface FlatPage {
+  title: string
+  i18nKey?: string
+  href: string
+  section?: string
+  sectionI18nKey?: string
+}
+
+function walkSubmenu(
+  items: SubMenuItem[],
+  section: string,
+  sectionI18nKey: string | undefined,
+  out: FlatPage[],
+) {
+  items.forEach((sub) => {
+    out.push({
+      title: sub.title,
+      i18nKey: sub.i18nKey,
+      href: sub.href,
+      section,
+      sectionI18nKey,
+    })
+    if (sub.submenu && sub.submenu.length > 0) {
+      walkSubmenu(sub.submenu, section, sectionI18nKey, out)
+    }
+  })
+}
+
 export function DocNavigation({ className }: DocNavigationProps) {
   const pathname = usePathname()
+  const tNav = useTranslations("docNav")
+  const tSidebar = useTranslations("docSidebar")
 
-  const flattenSidebarItems = () => {
-    const flatItems: Array<{ title: string; href: string; section?: string }> = []
+  const tItem = (i18nKey: string | undefined, fallback: string) => {
+    if (!i18nKey) return fallback
+    try {
+      return tSidebar(`items.${i18nKey}`)
+    } catch {
+      return fallback
+    }
+  }
+
+  const flattenSidebarItems = (): FlatPage[] => {
+    const flatItems: FlatPage[] = []
 
     sidebarItems.forEach((item) => {
       if (item.href) {
-        flatItems.push({ title: item.title, href: item.href })
+        flatItems.push({ title: item.title, i18nKey: item.i18nKey, href: item.href })
       }
 
       if (item.submenu) {
-        item.submenu.forEach((subItem) => {
-          flatItems.push({
-            title: subItem.title,
-            href: subItem.href,
-            section: item.title, 
-          })
-        })
+        walkSubmenu(item.submenu as SubMenuItem[], item.title, item.i18nKey, flatItems)
       }
     })
 
     return flatItems
   }
 
-  const allPages = flattenSidebarItems()
+  // Dedupe consecutive entries with the same href. Several sidebar
+  // sections (Post-Install, GPUs, Create VM, Disk Manager, …) have a
+  // parent whose href equals its first child's "Overview" href, so the
+  // flat sequence contains the same page twice in a row. Without dedup,
+  // Previous/Next on the parent would point to itself.
+  const rawPages = flattenSidebarItems()
+  const allPages: FlatPage[] = []
+  for (const p of rawPages) {
+    if (allPages.length > 0 && allPages[allPages.length - 1].href === p.href) continue
+    allPages.push(p)
+  }
 
   const currentPageIndex = allPages.findIndex((page) => page.href === pathname)
 
@@ -57,13 +113,16 @@ export function DocNavigation({ className }: DocNavigationProps) {
             <ChevronLeft className="h-5 w-5 mr-2 text-gray-500 group-hover:text-blue-500 flex-shrink-0" />
             <div className="min-w-0 overflow-hidden">
               <div className="text-sm text-gray-500 group-hover:text-blue-600 truncate">
-                {prevPage.section ? `${prevPage.section}: ` : ""}Previous
+                {prevPage.section ? `${tItem(prevPage.sectionI18nKey, prevPage.section)}: ` : ""}
+                {tNav("previous")}
+              </div>
+              <div className="font-medium group-hover:text-blue-700 truncate">
+                {tItem(prevPage.i18nKey, prevPage.title)}
               </div>
-              <div className="font-medium group-hover:text-blue-700 truncate">{prevPage.title}</div>
             </div>
           </Link>
         ) : (
-          <div className="hidden sm:block sm:w-[calc(50%-0.5rem)]"></div> 
+          <div className="hidden sm:block sm:w-[calc(50%-0.5rem)]"></div>
         )}
 
         {nextPage ? (
@@ -73,14 +132,17 @@ export function DocNavigation({ className }: DocNavigationProps) {
           >
             <div className="min-w-0 overflow-hidden">
               <div className="text-sm text-gray-500 group-hover:text-blue-600 truncate">
-                {nextPage.section ? `${nextPage.section}: ` : ""}Next
+                {nextPage.section ? `${tItem(nextPage.sectionI18nKey, nextPage.section)}: ` : ""}
+                {tNav("next")}
+              </div>
+              <div className="font-medium group-hover:text-blue-700 truncate">
+                {tItem(nextPage.i18nKey, nextPage.title)}
               </div>
-              <div className="font-medium group-hover:text-blue-700 truncate">{nextPage.title}</div>
             </div>
             <ChevronRight className="h-5 w-5 ml-2 text-gray-500 group-hover:text-blue-500 flex-shrink-0" />
           </Link>
         ) : (
-          <div className="hidden sm:block sm:w-[calc(50%-0.5rem)]"></div> 
+          <div className="hidden sm:block sm:w-[calc(50%-0.5rem)]"></div>
         )}
       </div>
     </div>