When multiple stopped events are detected we should send the `"allThreadsStopped":true` last. Currently, if there are multiple stopped threads and we attempt to step around the 'allThreadsStopped' ends up with multiple stops highlighted in the UI. Reporting the focused thread last fixes this while still correctly updating the thread state of all stopped threads. This fixes an issue reported in https://github.com/llvm/llvm-project/pull/176273#discussion_r2775979486