feat(shared-chat): support allowed_tools in tool_choice

packages/shared-chat/src/types/tool-choice.ts

@@ -1,4 +1,16 @@
-export type ToolChoice = 'auto' | 'none' | 'required' | {
-  function: { name: string }
+export type ToolChoice = AllowedTools | ToolChoiceMode | ToolChoiceTool
+
+interface AllowedTools {
+  mode: 'auto' | 'required'
+  tools: ToolChoiceTool[]
+  type: 'allowed_tools'
+}
+
+type ToolChoiceMode = 'auto' | 'none' | 'required'
+
+interface ToolChoiceTool {
+  function: {
+    name: string
+  }
   type: 'function'
 }