Windows Terminal key-binding offer preselected Yes; stray Enter rewrites Windows Terminal settings.json

Finding: In GitHub Copilot CLI 1.0.93 on Windows 10 22H2 (x64), an external report says that when WT_SESSION is set, startup shows a 'Set up terminal for multi-line input support' modal right after the folder-trust dialog, with '1. Yes' preselected. Per the reporter, the modal takes focus without any keystroke, so typed prompt letters are dropped and the first Enter accepts the offer. Copilot then adds a shift+enter sendInput action to the user's global Windows Terminal settings.json, writes a timestamped backup file, and the typed prompt is lost (source: https://github.com/github/copilot-cli/issues/5074). Reported conditions: the reporter hit this running the CLI in a pty-hosted terminal inside a desktop app launched from Windows Terminal, where WT_SESSION is inherited from the parent. They also describe a reproduction with a plain pty, LOCALAPPDATA pointed at a temp folder holding a stub Windows Terminal settings.json, a BYOK provider configuration, and a new folder. Sequence: answer the trust dialog with Enter, see the modal with Yes selected, type hello, press Enter. Reported result: a message that Windows Terminal key bindings were updated with shift+enter, the stub file gained the new actions entry, a backup appeared, and hello never reached the prompt (same source). The reporter's expected behavior is one of: default to No or require an explicit choice, show a non-modal hint pointing to /terminal-setup, or skip the offer when the CLI is not directly the Windows Terminal session (same source). The report also notes related issue #657 about /terminal-setup writing keybindings to the wrong file in containers. Possible mitigation (reporter-sourced, not verified): setting COPILOT_SETUP_TERMINAL=false disables the offer in the reporter's setup, and the reporter says it is not listed in copilot help environment. Whether it works across versions or setups is unknown. Status: no maintainer response, confirmed cause, fix commit, or released fix appears in the supplied data, and comments coverage is limited to the issue body. This is an external report; Kilo/KFA did not reproduce it. Diagnostic takeaway: if a Windows Terminal settings.json unexpectedly gains a shift+enter action after launching Copilot CLI from a nested terminal that inherits WT_SESSION, this offer is a reported cause; the backup file the reporter mentions is a possible way to compare changes.