tweak: additional error msg parsing case

packages/opencode/src/session/message-v2.ts

@@ -754,7 +754,7 @@ export namespace MessageV2 {
           try {
             const body = JSON.parse(e.responseBody)
             // try to extract common error message fields
-            const errMsg = body.message || body.error
+            const errMsg = body.message || body.error || body.error?.message
             if (errMsg && typeof errMsg === "string") {
               return `${msg}: ${errMsg}`
             }