Using DAP OutputEvent over stderr for results

Prerequisites

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Summary

Currently it seems output streams of the debugee are routed to stderr of the editor services. Is there a reason DAP OutputEvent are not being used for this?
Context:
https://github.com/mfussenegger/nvim-dap/discussions/1419#discussioncomment-11893631
The DAP client for nvim recently started routing stderr of debug server to logfiles rather than showing it to users. This change on client side now prevents me from seeing the outputs streams of my debugee in neovim. Apparently most debug servers use OutputEvent to communicate output streams, so clients will be more likely to have support for this!

Proposed Design

Use OutputEvent to communicate the output streams rather than stderr.

该 issue 未指定文件或测试。首先跟踪 debugee 输出流在调试集成中如何路由到 stderr，然后检查 DAP output events 的处理；当这些流通过 OutputEvent 进行传递且不丢失 Neovim 可见的输出时，即视为完成。