Fix Claude Sonnet 4 model ID (#31505)

This PR is a follow-up to
https://github.com/zed-industries/zed/pull/31415 that fixes the model ID
for Claude Sonnet 4.

With the release of the Claude 4 models, the model version now appears
at the end.

Release Notes:

- N/A

assets/settings/default.json

@@ -729,14 +729,14 @@
       // The provider to use.
       "provider": "zed.dev",
       // The model to use.
-      "model": "claude-4-sonnet"
+      "model": "claude-sonnet-4"
     },
     // The model to use when applying edits from the agent.
     "editor_model": {
       // The provider to use.
       "provider": "zed.dev",
       // The model to use.
-      "model": "claude-4-sonnet"
+      "model": "claude-sonnet-4"
     },
     // Additional parameters for language model requests. When making a request to a model, parameters will be taken
     // from the last entry in this list that matches the model's provider and name. In each entry, both provider
@@ -756,7 +756,7 @@
       // To set parameters for a specific provider and model:
       // {
       //   "provider": "zed.dev",
-      //   "model": "claude-4-sonnet",
+      //   "model": "claude-sonnet-4",
       //   "temperature": 1.0
       // }
     ],