fix(tools): make schema traversal stack-safe

packages/core/tools/src/index.ts

@@ -773,10 +773,14 @@ export class ToolRegistry extends Service {
   /** Project one definition onto the model-facing schema fields. */
   private schemaOf(definition: ToolDefinition, detachParameters: boolean): ToolSchema {
     const { name, description, parameters } = definition
+    const detached = detachParameters ? snapshotJsonValue(parameters) : parameters
+    if (detached === undefined) {
+      throw new Error(`tool "${name}" parameters must be lossless JSON before schema projection`)
+    }
     return {
       name,
       description,
-      parameters: detachParameters ? structuredClone(parameters) : parameters,
+      parameters: detached,
     }
   }