Bump nextra-theme-docs from 4.0.9 to 4.2.1

Bumps [nextra-theme-docs](https://github.com/shuding/nextra) from 4.0.9 to 4.2.1.
- [Release notes](https://github.com/shuding/nextra/releases)
- [Commits](https://github.com/shuding/nextra/compare/[email protected]@4.2.1)

---
updated-dependencies:
- dependency-name: nextra-theme-docs
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.yarn/cache/nextra-theme-docs-npm-4.0.9-744ea80191-4cbb891fff.zip

@@ -12,7 +12,7 @@
   "dependencies": {
     "next": "^15.1.6",
     "nextra": "^4.0.9",
-    "nextra-theme-docs": "^4.0.9",
+    "nextra-theme-docs": "^4.2.1",
     "react": "^18.3.1",
     "react-dom": "^18.3.1",
     "react-icons": "^5.4.0"

.yarn/cache/nextra-theme-docs-npm-4.2.1-b091d461a3-a1c3e56ed7.zip

@@ -1357,7 +1357,7 @@ __metadata:
     "@types/react": "npm:^18.3.18"
     next: "npm:^15.1.6"
     nextra: "npm:^4.0.9"
-    nextra-theme-docs: "npm:^4.0.9"
+    nextra-theme-docs: "npm:^4.2.1"
     pagefind: "npm:^1.3.0"
     prettier: "npm:^3.4.2"
     react: "npm:^18.3.1"
@@ -3789,9 +3789,9 @@ __metadata:
   languageName: node
   linkType: hard
 
-"nextra-theme-docs@npm:^4.0.9":
-  version: 4.0.9
-  resolution: "nextra-theme-docs@npm:4.0.9"
+"nextra-theme-docs@npm:^4.2.1":
+  version: 4.2.1
+  resolution: "nextra-theme-docs@npm:4.2.1"
   dependencies:
     "@headlessui/react": "npm:^2.1.2"
     clsx: "npm:^2.1.0"
@@ -3803,10 +3803,10 @@ __metadata:
     zustand: "npm:^5.0.1"
   peerDependencies:
     next: ">=14"
-    nextra: 4.0.9
+    nextra: 4.2.1
     react: ">=18"
     react-dom: ">=18"
-  checksum: 10c0/4cbb891fff984dd41262ced3d2ddf885b1e24e1a8bfb72cb6d48f336de304a2af16b3218682b9b1546ace2370633117ae2a5dd4614ab30026e66abb170a1d4bf
+  checksum: 10c0/a1c3e56ed7a0d04bd29d476bf959d20b0abb4abb6e2484b3313e25c05fe340f06934790c1354c19b41b6c4c1c720d6529fa4e30e3696ce29133aba5e2cd63e5b
   languageName: node
   linkType: hard