Add Windows installer packaging (Setup.exe + portable exe)

PyInstaller onedir/onefile specs, Inno Setup script, and GitHub Actions
workflow to produce JUC500-Setup-win64.exe and portable builds.

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

scripts/setup_macos.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+set -euo pipefail
+ROOT="$(cd "$(dirname "$0")/.." && pwd)"
+cd "$ROOT"
+
+if ! command -v brew >/dev/null 2>&1; then
+  echo "Homebrew 가 필요합니다: https://brew.sh"
+  exit 1
+fi
+
+brew list libusb >/dev/null 2>&1 || brew install libusb
+
+python3 -m venv .venv
+# shellcheck disable=SC1091
+source .venv/bin/activate
+pip install -U pip
+pip install -r requirements.txt
+pip install -e .
+
+echo
+echo "설치 완료. 예:"
+echo "  source $ROOT/.venv/bin/activate"
+echo "  juc500 info"
+echo "  juc500 recv -y --dest ~/Downloads"
+echo "  juc500 send /path/to/file"

scripts/setup_windows.bat

@@ -0,0 +1,16 @@
+@echo off
+setlocal
+cd /d %~dp0..
+
+py -3 -m venv .venv
+call .venv\Scripts\activate.bat
+python -m pip install -U pip
+pip install -r requirements.txt
+pip install -e .
+
+echo.
+echo Setup done. Next:
+echo   .venv\Scripts\activate
+echo   python -m juc500_xfer info
+echo See docs\WINDOWS.md for Zadig / WinUSB steps.
+endlocal