Create MSIX Windows installer

The winget package manager requires installers. It cannot install .exe
files itself. Create an MSIX-based installer for quick-lint-js. This
MSIX installer will be used in the future to add quick-lint-js to
winget.

Also, add code to sign a MSIX file. This requires a lot of code because
Go's archive/zip package produces ZIP files which can't be read by
Microsoft's APPX/MSIX installer stuff for some reason, and because we
need to recreate AppxBlockMap.xml when swapping out quick-lint-js.exe.

Author: strager

.editorconfig

@@ -37,7 +37,7 @@ indent_style = tab
 max_line_length = off
 
 # Keep in sync with Prettier.
-[*.{css,html,js,json,mjs}]
+[*.{css,html,js,json,mjs,xml}]
 indent_size = 2
 indent_style = space
 max_line_length = 80

.github/workflows/build-static.yml

@@ -347,6 +347,44 @@ jobs:
           remote-directory: ${{ secrets.artifacts_root }}/builds/${{ github.sha }}/scoop/
           user: ${{ secrets.artifacts_user }}
 
+  package-msix:
+    name: MSIX installer
+    needs: build
+    runs-on: windows-2022
+    steps:
+      - name: checkout
+        uses: actions/checkout@v2
+      - uses: actions/download-artifact@v2
+        with:
+          name: quick-lint-js-windows-${{ github.sha }}
+          path: ./
+
+      - name: extract ZIP
+        run: Expand-Archive -LiteralPath windows.zip -DestinationPath quick-lint-js
+        shell: powershell
+
+      - name: create MSIX
+        run: |
+          PATH="${PATH}:/c/Program Files (x86)/Windows Kits/10/App Certification Kit"
+          go run ./dist/msix/build-unsigned-msix.go -EXE ./quick-lint-js/bin/quick-lint-js.exe -License ./quick-lint-js/share/doc/quick-lint-js/copyright -Out quick-lint-js.msix
+        shell: bash
+
+      - name: upload MSIX to workflow
+        uses: actions/upload-artifact@v2
+        with:
+          if-no-files-found: error
+          name: quick-lint-js-msix-${{ github.sha }}
+          path: quick-lint-js.msix
+      - name: upload MSIX to long-term storage
+        if: ${{ github.event_name == 'push' && github.repository_owner == 'quick-lint' != null }}
+        uses: quick-lint/sftp-upload@master
+        with:
+          host: ${{ secrets.artifacts_host }}
+          local-file-globs: quick-lint-js.msix
+          private-key: ${{ secrets.artifacts_key }}
+          remote-directory: ${{ secrets.artifacts_root }}/builds/${{ github.sha }}/windows/
+          user: ${{ secrets.artifacts_user }}
+
 # quick-lint-js finds bugs in JavaScript programs.
 # Copyright (C) 2020  Matthew Glazar
 #