Merge pull request #468 from s-Joshua-s/fix/thinking-block-modification-error

fix(api): 修复 thinking 块被意外修改导致的 400 错误

backend/internal/service/antigravity_gateway_service.go

@@ -1168,6 +1168,12 @@ func isSignatureRelatedError(respBody []byte) bool {
 		return true
 	}
 
+	// Detect thinking block modification errors:
+	// "thinking or redacted_thinking blocks in the latest assistant message cannot be modified"
+	if strings.Contains(msg, "cannot be modified") && (strings.Contains(msg, "thinking") || strings.Contains(msg, "redacted_thinking")) {
+		return true
+	}
+
 	return false
 }