Merge pull request #9710 from ncdai/docs/registry-item-json

docs: add devDependencies section to registry-item-json.mdx

apps/v4/content/docs/registry/registry-item-json.mdx

@@ -18,6 +18,7 @@ The `registry-item.json` schema is used to define your custom registry items.
     "https://example.com/r/foo"
   ],
   "dependencies": ["is-even@3.0.0", "motion"],
+  "devDependencies": ["tw-animate-css"],
   "files": [
     {
       "path": "registry/new-york/hello-world/hello-world.tsx",
@@ -144,6 +145,21 @@ Use `@version` to specify the version of your registry item.
 }
 ```
 
+### devDependencies
+
+The `devDependencies` property is used to specify the dev dependencies of your registry item. These are `npm` packages that are only needed during development.
+
+Use `@version` to specify the version of the package.
+
+```json title="registry-item.json" showLineNumbers
+{
+  "devDependencies": [
+    "tw-animate-css",
+    "name@1.2.0"
+  ]
+}
+```
+
 ### registryDependencies
 
 Used for registry dependencies. Can be names, namespaced or URLs.