Add Xai model

app/constant.ts

@@ -585,7 +585,16 @@ const iflytekModels = [
 
 const deepseekModels = ["deepseek-chat", "deepseek-coder", "deepseek-reasoner"];
 
-const xAIModes = ["grok-beta"];
+const xAIModes = [
+  "grok-beta",
+  "grok-2",
+  "grok-2-1212",
+  "grok-2-latest",
+  "grok-vision-beta",
+  "grok-2-vision-1212",
+  "grok-2-vision",
+  "grok-2-vision-latest",
+];
 
 const chatglmModels = [
   "glm-4-plus",