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.

この Issue ではファイルやテストは指定されていません。まず、デバッグ統合で debugee の出力ストリームが stderr にどのようにルーティングされているかを追跡し、次に DAP output events の処理を確認してください。これらのストリームが Neovim から見える出力を失わずに OutputEvent を通じて伝達されれば完了です。