404 footer navbar (#2219)

## Description

| light | dark |
| ---- | ---- |
| <img width="1489" height="881" alt="image"
src="https://github.com/user-attachments/assets/c850afe5-6132-4a16-8c7b-af4a44b094fa"
/> | <img width="1482" height="882" alt="image"
src="https://github.com/user-attachments/assets/24f3f11a-529f-4757-814b-2b59844f2b69"
/> |

Also made the text match highlight bright neutral with underline (like
in Fumadocs) instead of primary as it's more legible on blurred
background.

<img width="633" height="451" alt="image"
src="https://github.com/user-attachments/assets/d89a815b-2684-407e-b1e1-adce484221d4"
/>


Added a navbar and footer to the 404 page.

Had to eject the search input from Nextra (but we talked with designers
about restyling it anyway, so this is a first step.).

Author: hasparus

package.json

@@ -3,7 +3,7 @@
   "type": "module",
   "repository": "graphql/graphql.github.io website",
   "private": true,
-  "packageManager": "pnpm@10.16.1+sha512.0e155aa2629db8672b49e8475da6226aa4bdea85fdcdfdc15350874946d4f3c91faaf64cbdc4a5d1ab8002f473d5c3fcedcd197989cf0390f9badd3c04678706",
+  "packageManager": "pnpm@10.20.0+sha512.cf9998222162dd85864d0a8102e7892e7ba4ceadebbf5a31f9c2fce48dfce317a9c53b9f6464d1ef9042cba2e02ae02a9f7c143a2b438cd93c91840f0192b9dd",
   "scripts": {
     "analyze": "ANALYZE=true next build",
     "build": "next build",
@@ -47,7 +47,9 @@
     "clsx": "^2.1.1",
     "cm6-graphql": "^0.2.1",
     "date-fns": "^2.30.0",
+    "escape-string-regexp": "^5.0.0",
     "fast-glob": "^3.3.3",
+    "flexsearch": "0.7.43",
     "github-slugger": "2.0.0",
     "graphql": "16.10.0",
     "gray-matter": "^4.0.3",

patches/nextra-theme-docs.patch

@@ -1,8 +1,16 @@
 diff --git a/dist/index.d.mts b/dist/index.d.mts
-index 71f87bcd1dde49d7c19ad49fc098e715a76c5c10..53dffe4fbe5fb2a92cb55a0466bf95315f904e4e 100644
+index 71f87bcd1dde49d7c19ad49fc098e715a76c5c10..a0b8143b6b7ef89513c2199b956f5f87c79c3d45 100644
 --- a/dist/index.d.mts
 +++ b/dist/index.d.mts
-@@ -1421,3 +1421,24 @@ declare function ThemeSwitch({ lite, className }: ThemeSwitchProps): ReactElemen
+@@ -1248,6 +1248,7 @@ interface Menu {
+     setMenu: Dispatch<SetStateAction<boolean>>;
+ }
+ declare const useMenu: () => Menu;
++export declare const MenuProvider: (props: { value: Menu; children: ReactNode; }) => JSX.Element;
+ 
+ declare const useThemeConfig: () => {
+     banner: {
+@@ -1421,3 +1422,24 @@ declare function ThemeSwitch({ lite, className }: ThemeSwitchProps): ReactElemen
  declare function Layout({ children, themeConfig, pageOpts }: NextraThemeLayoutProps): ReactElement;
 
  export { Bleed, Collapse, type PartialDocsThemeConfig as DocsThemeConfig, Link, LocaleSwitch, Navbar, NotFoundPage, SkipNavContent, SkipNavLink, ThemeSwitch, Layout as default, getComponents, useConfig, useMenu, useThemeConfig };
@@ -28,7 +36,7 @@ index 71f87bcd1dde49d7c19ad49fc098e715a76c5c10..53dffe4fbe5fb2a92cb55a0466bf9531
 +  flatDocsDirectories: Item[]
 +}
 diff --git a/dist/index.js b/dist/index.js
-index 56201641fd965dcc5ab7c5df53e444c41293c00e..29a446663f5d24acad0389f873c5e31be910717c 100644
+index 56201641fd965dcc5ab7c5df53e444c41293c00e..71f4d353b5bd6c0fcab630330f578b5593f8596e 100644
 --- a/dist/index.js
 +++ b/dist/index.js
 @@ -100,10 +100,10 @@ IntersectionObserverContext.displayName = "IntersectionObserver";
@@ -46,6 +54,15 @@ index 56201641fd965dcc5ab7c5df53e444c41293c00e..29a446663f5d24acad0389f873c5e31b
  var ActiveAnchorProvider = ({
    children
  }) => {
+@@ -173,7 +173,7 @@ var MenuContext = createContext2({
+ });
+ MenuContext.displayName = "Menu";
+ var useMenu = () => useContext2(MenuContext);
+-var MenuProvider = MenuContext.Provider;
++export var MenuProvider = MenuContext.Provider;
+ 
+ // src/contexts/config.tsx
+ import { jsx as jsx3 } from "react/jsx-runtime";
 @@ -520,44 +520,6 @@ function Bleed({
    );
  }