Phase 2: MSIX 패키지 + IExplorerCommand 셸 익스텐션

C++ 셸 익스텐션 (src/EverythingToJpeg.Shell/)
- WRL RuntimeClass 패턴으로 IExplorerCommand 두 핸들러 구현
- Quick(빠른 변환) / Dialog(설정 창) verb를 다른 CLSID로 분리
- Invoke()에서 EverythingToJpeg.exe로 verb + 파일 경로 전달
- VS 2026 빌드 검증, /utf-8 한글 라벨 지원

MSIX 패키징 (packaging/)
- Package.appxmanifest: com:SurrogateServer + desktop4:FileExplorerContextMenus
- 26개 확장자 × 2 verb 자동 노출
- BuildMsix.ps1: dotnet publish + msbuild + makeappx 일관 파이프라인
- CreateDevCert.ps1 / Install-EverythingToJpeg.ps1: 자체 서명 인증서 워크플로
- GenerateAssets.ps1: placeholder 로고 자동 생성

CI/CD
- .github/workflows/release.yml: 태그 푸시 시 미서명 MSIX 자동 빌드 + 첨부

검증
- 50MB MSIX 산출 확인 (packaging/dist/EverythingToJpeg-x64.msix)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packaging/GenerateAssets.ps1

@@ -0,0 +1,56 @@
+#Requires -Version 5.1
+# packaging/Assets/ 의 placeholder 아이콘들을 생성한다.
+# 추후 진짜 로고로 교체.
+
+$ErrorActionPreference = 'Stop'
+Add-Type -AssemblyName System.Drawing
+
+$assetsDir = Join-Path $PSScriptRoot 'Assets'
+if (-not (Test-Path $assetsDir)) { New-Item -ItemType Directory -Path $assetsDir | Out-Null }
+
+function New-LogoPng {
+    param(
+        [int]$Width,
+        [int]$Height,
+        [string]$Path,
+        [string]$Label = ''
+    )
+    $bmp = New-Object System.Drawing.Bitmap($Width, $Height, [System.Drawing.Imaging.PixelFormat]::Format32bppArgb)
+    $g = [System.Drawing.Graphics]::FromImage($bmp)
+    $g.SmoothingMode = [System.Drawing.Drawing2D.SmoothingMode]::AntiAlias
+    $g.TextRenderingHint = [System.Drawing.Text.TextRenderingHint]::ClearTypeGridFit
+
+    $rect = New-Object System.Drawing.Rectangle(0, 0, $Width, $Height)
+    $brush = New-Object System.Drawing.Drawing2D.LinearGradientBrush(
+        $rect,
+        [System.Drawing.Color]::FromArgb(0xFF, 0x3B, 0x82, 0xF6),
+        [System.Drawing.Color]::FromArgb(0xFF, 0x1E, 0x40, 0xAF),
+        [System.Drawing.Drawing2D.LinearGradientMode]::Diagonal)
+    $g.FillRectangle($brush, $rect)
+
+    if ($Label) {
+        $fontSize = [Math]::Max(8, [Math]::Min($Width, $Height) / 5)
+        $font = New-Object System.Drawing.Font('Segoe UI', $fontSize, [System.Drawing.FontStyle]::Bold)
+        $textBrush = [System.Drawing.Brushes]::White
+        $sf = New-Object System.Drawing.StringFormat
+        $sf.Alignment = [System.Drawing.StringAlignment]::Center
+        $sf.LineAlignment = [System.Drawing.StringAlignment]::Center
+        $rectF = New-Object System.Drawing.RectangleF(0, 0, [float]$Width, [float]$Height)
+        $g.DrawString($Label, $font, $textBrush, $rectF, $sf)
+        $font.Dispose()
+        $sf.Dispose()
+    }
+
+    $g.Dispose()
+    $bmp.Save($Path, [System.Drawing.Imaging.ImageFormat]::Png)
+    $bmp.Dispose()
+    $brush.Dispose()
+    Write-Host "  [+] $Path ($Width x $Height)"
+}
+
+Write-Host 'Generating placeholder logos…'
+New-LogoPng -Width 50  -Height 50  -Path (Join-Path $assetsDir 'StoreLogo.png')        -Label 'E2J'
+New-LogoPng -Width 44  -Height 44  -Path (Join-Path $assetsDir 'Square44x44Logo.png')  -Label 'E2J'
+New-LogoPng -Width 150 -Height 150 -Path (Join-Path $assetsDir 'Square150x150Logo.png')-Label 'E2J'
+New-LogoPng -Width 310 -Height 150 -Path (Join-Path $assetsDir 'Wide310x150Logo.png')  -Label 'EverythingToJpeg'
+Write-Host 'Done.'