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/messages/en/docs/about/index.json

@@ -0,0 +1,67 @@
+{
+  "meta": {
+    "title": "About | ProxMenux Documentation",
+    "description": "About ProxMenux: project goals, contributors, FAQ and Code of Conduct. Open-source menu-driven management tool for Proxmox VE 8+, built and maintained by MacRimi with a small team of testers and contributors.",
+    "ogTitle": "About | ProxMenux Documentation",
+    "ogDescription": "About ProxMenux — open-source menu-driven management tool for Proxmox VE 8+."
+  },
+  "header": {
+    "title": "About",
+    "description": "Project info, FAQ, contributors and code of conduct. ProxMenux is an open-source menu-driven management tool for Proxmox VE 8+, built and maintained by MacRimi with the help of a small team of testers and contributors.",
+    "section": "About"
+  },
+  "callout": {
+    "title": "Open source, community-driven",
+    "body": "ProxMenux is GPL-3.0 licensed and developed in the open on GitHub. Every script is reviewable, every change traceable. Contributions — bug reports, ideas, code, testing — are welcome."
+  },
+  "section": {
+    "heading": "In this section",
+    "options": [
+      {
+        "icon": "HelpCircle",
+        "href": "/docs/about/faq",
+        "title": "FAQ",
+        "description": "Frequently asked questions: what ProxMenux is, install, compatibility, customisation, updates, security, production use, uninstall."
+      },
+      {
+        "icon": "Users",
+        "href": "/docs/about/contributors",
+        "title": "Contributors",
+        "description": "Recognition for the people who make ProxMenux possible — testers, reviewers and developers who shape each release."
+      },
+      {
+        "icon": "ScrollText",
+        "href": "/docs/about/code-of-conduct",
+        "title": "Code of Conduct",
+        "description": "Project values, code-responsibility expectations and contribution guidelines. Required reading before opening a PR or report."
+      }
+    ]
+  },
+  "involved": {
+    "heading": "Get involved",
+    "intro": "Three places to engage with the project:",
+    "cards": [
+      {
+        "href": "https://github.com/MacRimi/ProxMenux/issues/new",
+        "title": "🐛 Report a bug",
+        "description": "GitHub Issues — include logs and reproduction steps."
+      },
+      {
+        "href": "https://github.com/MacRimi/ProxMenux/discussions",
+        "title": "💡 Suggest a feature",
+        "description": "GitHub Discussions — share ideas before opening a PR."
+      },
+      {
+        "href": "https://github.com/MacRimi/ProxMenux/pulls",
+        "title": "🔀 Submit a PR",
+        "description": "GitHub Pull Requests — read the Code of Conduct first."
+      }
+    ]
+  },
+  "support": {
+    "heading": "Support the project",
+    "introRich": "If ProxMenux saves you time, the easiest way to help others discover it is to <starlink>give the repo a ⭐ on GitHub</starlink>. If you want to go further:",
+    "kofiLabel": "Support on Ko-fi",
+    "kofiOutro": " — buys the maintainer a coffee and keeps development going."
+  }
+}