docs: recommend v6 codemod command for v5 to v6 migration (#11400)

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Author: dancer

content/docs/08-migration-guides/24-migration-guide-6-0.mdx

@@ -37,19 +37,18 @@ Codemods are transformations that run on your codebase automatically. They
 allow you to easily apply many changes without having to manually go through
 every file.
 
-You can run all codemods provided as part of the 6.0 upgrade process by running
-the following command from the root of your project:
-
-```sh
-npx @ai-sdk/codemod upgrade
-```
-
-To run only the v6 codemods (v5 → v6 migration):
+You can run all v6 codemods (v5 → v6 migration) by running the following command
+from the root of your project:
 
 ```sh
 npx @ai-sdk/codemod v6
 ```
 
+<Note>
+  There is also an `npx @ai-sdk/codemod upgrade` command, but it runs all
+  codemods from all versions (v4, v5, and v6). Use `v6` when upgrading from v5.
+</Note>
+
 Individual codemods can be run by specifying the name of the codemod:
 
 ```sh