Removes codex networks, removes "join the testnet" on main page

.vitepress/config.mts

@@ -119,14 +119,6 @@ export default withMermaid({
           { text: 'Troubleshoot', link: '/learn/troubleshoot' }
         ]
       },
-      {
-        text: 'Codex networks',
-        collapsed: false,
-        items: [
-          { text: 'Devnet', link: '/networks/devnet' },
-          { text: 'Testnet', link: '/networks/testnet' }
-        ]
-      },
       {
         text: 'Developers',
         collapsed: false,
@@ -310,13 +302,6 @@ export default withMermaid({
               { text: '문제 해결', link: '/ko/learn/troubleshoot' }
             ]
           },
-          {
-            text: 'Codex networks',
-            collapsed: false,
-            items: [
-              { text: '테스트넷', link: '/ko/networks/testnet' }
-            ]
-          },
           {
             text: 'Developers',
             collapsed: false,

README.md

@@ -74,7 +74,6 @@
 
  Project structure
  - `learn` - All information to learn about Codex
- - `networks` - Codex networks related information
  - `developers` - Codex development process and guides
 
 

index.md

@@ -13,9 +13,6 @@ hero:
     - theme: alt
       text: Quick start
       link: /learn/quick-start
-    - theme: alt
-      text: Join Codex Testnet
-      link: /networks/testnet
 
 features:
   - title: Learn