Protocol response formatting

When implementing terminal protocol responses (CSI, DCS, OSC sequences), ensure proper formatting with correct terminators and maintain protocol transparency. Terminal protocols require specific response formats with appropriate terminators - CSI responses should use the same C1 mode as the request, DCS responses need proper DCS/ST framing, and OSC...

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When implementing terminal protocol responses (CSI, DCS, OSC sequences), ensure proper formatting with correct terminators and maintain protocol transparency. Terminal protocols require specific response formats with appropriate terminators - CSI responses should use the same C1 mode as the request, DCS responses need proper DCS/ST framing, and OSC responses should echo the same terminator (BEL or ST) as the requesting sequence.

For example, when handling terminal state reports:

void AdaptDispatch::_ReturnDcsResponse(const std::wstring_view response) const
{
    const auto dcs = _terminalInput.GetInputMode(TerminalInput::Mode::SendC1) ? L"\x90" : L"\x1BP";
    const auto st = _terminalInput.GetInputMode(TerminalInput::Mode::SendC1) ? L"\x9C" : L"\x1B\\";
    _api.ReturnResponse(fmt::format(FMT_COMPILE(L"{}{}{}"), dcs, response, st));
}

Additionally, maintain protocol transparency by avoiding reactions to sequences that should be handled by the terminal client. ConPTY should not react to sequences like “CSI 1 t” or “CSI 2 t” for show/hide operations, as these are the terminal’s responsibility. This prevents double-processing and maintains the expected protocol behavior between terminal and application.

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