初始提交：terminalX 可运行态（M0/M1/M1.5 已真机验证）

- M0: libghostty SSH 终端（渲染/输入/连接）+ 白屏修复(OutputGate) + 会话状态机/自动重连
- M1: tsnet 用户态组网 + SSH-over-tsnet(fd 桥)，shell 级真机验证；R5(Go+gvisor+C+++Swift 同进程) retire
- M1.5: tmux -CC 原生 tab（MVP）
- 结构: packages/(TXCore·TXTransport), apps/TerminalX, vendor/(libghostty-spm/libssh2/mbedtls/tsnet-bridge), artifacts/
- 文档: CLAUDE.md + docs/HANDOFF.md（新会话入口）
- 环境: 认证代理→依赖 vendor 本地化；Go 在 ~/.local/go；仅模拟器/未签名
- 待续: M2 mosh, tmux 多 pane, M4 安全(host key/SE)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

vendor/libssh2/docs/libssh2_channel_signal_ex.3

@@ -0,0 +1,32 @@
+.\" Copyright (C) The libssh2 project and its contributors.
+.\" SPDX-License-Identifier: BSD-3-Clause
+.TH libssh2_channel_signal_ex 3 "20 Apr 2023" "libssh2 1.11.0" "libssh2"
+.SH NAME
+libssh2_channel_signal_ex -- Send a signal to process previously opened on channel.
+.SH SYNOPSIS
+.nf
+#include <libssh2.h>
+
+int
+libssh2_channel_signal_ex(LIBSSH2_CHANNEL *channel,
+                          const char *signame,
+                          size_t signame_len)
+.fi
+.SH DESCRIPTION
+A signal can be delivered to the remote process/service. Some servers or
+systems may not implement signals, in which case they will probably ignore this
+message.
+
+\fIchannel\fP - Previously opened channel instance such as returned by
+.BR libssh2_channel_open_ex(3)
+
+\fIsigname\fP - The signal name is the same as the signal name constant, without the leading "SIG".
+
+\fIsigname_len\fP - Length of passed signal name parameter.
+
+There is also a macro \fIlibssh2_channel_signal(channel, signame)\fP that supplies the strlen of the signame.
+.SH RETURN VALUE
+Normal channel error codes.
+LIBSSH2_ERROR_EAGAIN when it would block.
+.SH SEE ALSO
+.BR libssh2_channel_get_exit_signal(3)