Initial CST-Agent: portable Linux/Termux/Windows coding agent.

Vendored sashidown, OpenAI-compatible env (OPENAI_*), and bootstrap scripts.

Co-authored-by: Cursor <cursoragent@cursor.com>

scripts/bootstrap_windows.sh

@@ -0,0 +1,48 @@
+#!/usr/bin/env bash
+# One-shot on a Linux host: cross-build Windows x86_64 release (MinGW).
+# Output: dist/windows-x86_64/  — copy that folder to a Windows machine.
+set -euo pipefail
+
+REPO_URL="${CST_AGENT_REPO:-https://git.whcself.xyz/WHC/CST-agent.git}"
+DIR="${1:-}"
+
+if [[ -z "$DIR" ]]; then
+  if [[ -f CMakeLists.txt && -d src ]]; then
+    DIR="$(pwd)"
+  else
+    DIR="CST-agent"
+  fi
+fi
+
+if [[ ! -f "$DIR/CMakeLists.txt" ]]; then
+  echo "==> git clone $REPO_URL -> $DIR"
+  git clone "$REPO_URL" "$DIR"
+fi
+cd "$DIR"
+
+need() { command -v "$1" >/dev/null || { echo "missing $1 (install mingw-w64 gcc cmake git)" >&2; exit 1; }; }
+need git; need cmake; need x86_64-w64-mingw32-gcc
+
+echo "==> third-party (curl Schannel + PDCurses + busybox-w32)"
+chmod +x scripts/*.sh 2>/dev/null || true
+./scripts/build_third_party_mingw.sh all
+
+echo "==> cmake Windows TUI"
+cmake -B build-win-tui \
+  -DCMAKE_TOOLCHAIN_FILE=cmake/mingw-w64-x86_64.cmake \
+  -DCST_BUILD_TUI=ON \
+  -DCMAKE_PREFIX_PATH="$PWD/third_party/prefix-mingw" \
+  -DPDCurses_ROOT="$PWD/third_party/prefix-mingw"
+cmake --build build-win-tui -j"$(nproc 2>/dev/null || echo 4)"
+
+echo "==> package"
+./scripts/package_windows.sh
+
+echo
+echo "OK: dist/windows-x86_64/"
+echo "Copy that folder to Windows, then:"
+echo "  set OPENAI_API_KEY=sk-..."
+echo "  set OPENAI_BASE_URL=https://api.openai.com/v1"
+echo "  set OPENAI_MODEL=gpt-4.1-mini"
+echo "  cst-agent.exe --workspace ."
+echo "See docs/env_openai.md and docs/README-windows.md"