docs(mcp): correct capitalization of CODEX tab in documentation

Author: chishiyac

apps/www/content/docs/mcp.mdx

@@ -28,7 +28,7 @@ This is useful for Magic UI because you can now give your AI-assisted IDE direct
     <TabsTrigger value="cursor">Cursor</TabsTrigger>
     <TabsTrigger value="windsurf">Windsurf</TabsTrigger>
     <TabsTrigger value="claude">Claude</TabsTrigger>
-    <TabsTrigger value="codex">CODEX</TabsTrigger>
+    <TabsTrigger value="codex">Codex</TabsTrigger>
     <TabsTrigger value="cline">Cline</TabsTrigger>
     <TabsTrigger value="roo-cline">Roo-Cline</TabsTrigger>
   </TabsList>