Publish a Windows setup beside the AppImage and the disk image

The releases page had nothing for Windows, so the only way in was a
checkout, a Python and a pip install. What goes out now is one setup
program per release: PyInstaller's directory, the pinned ffmpeg the
disk image already uses, and Inno Setup around both. It installs for
the account alone, so no administrator is asked for.

Two executables over the one program there, because a windowed one on
Windows has no standard output at all: Dikte.exe for the Start Menu and
dikte.exe for the terminal, sharing everything they carry. The icon is
drawn by Dikte itself into an .ico, the way the Mac's .icns and Linux's
PNGs already are, so there is still no image file in the repository.

Starting at sign-in is a registry value rather than a Startup shortcut,
which is what lets the setup program, the uninstaller and
`dikte integrate` all mean the same thing: the wizard asks once, and
typing the command changes the answer later.

The three builds move into build.yml, which release.yml now calls
instead of holding its own copy, and which a pull request touching the
packaging runs on its own. A broken build is then a red pull request
rather than a failed release.

.github/workflows/release.yml

@@ -107,70 +107,16 @@ jobs:
           esac
           echo "version=$version" >> "$GITHUB_OUTPUT"
 
+  # The builds themselves are build.yml, which a pull request touching the
+  # packaging also runs on its own. One definition, so the download somebody
+  # gets from a release and the one a pull request was checked against cannot
+  # come out of two different sets of steps.
   build:
     needs: version
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-          # The oldest Ubuntu still offered, because the glibc a build links
-          # against is the oldest one it will run on, and 22.04's covers every
-          # distribution released since. Move it up only when it goes away.
-          - os: ubuntu-22.04
-            kind: appimage
-          - os: macos-latest
-            kind: dmg
-          # Intel Macs. This runner is the last x86_64 image Actions will
-          # offer, and it goes away in August 2027.
-          - os: macos-15-intel
-            kind: dmg
-
-    runs-on: ${{ matrix.os }}
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          ref: ${{ needs.version.outputs.ref }}
-
-      - uses: actions/setup-python@v5
-        with:
-          python-version: "3.12"
-
-      # PyQt6 ships Qt itself, but Qt still loads these from the system, and
-      # the build draws its own icon before it packages anything.
-      - name: Install the Qt runtime libraries
-        if: runner.os == 'Linux'
-        run: |
-          sudo apt-get update
-          sudo apt-get install --no-install-recommends -y \
-            libegl1 libgl1 libxkbcommon0 libdbus-1-3 libglib2.0-0 \
-            libfontconfig1 libfreetype6 libgssapi-krb5-2
-
-      - name: Install PyQt6 and PyInstaller
-        run: python -m pip install --quiet PyQt6 pyinstaller
-
-      # Only for the builds off master: a tagged build already says the number
-      # it was tagged with, and rewriting it would be rewriting the tag.
-      - name: Write the version being built
-        if: needs.version.outputs.prerelease == 'true'
-        env:
-          VERSION: ${{ needs.version.outputs.version }}
-        run: |
-          python - <<'PY'
-          import os, pathlib, re
-          path = pathlib.Path("dikte/__init__.py")
-          path.write_text(re.sub(r'^__version__ = ".*"$',
-                                 f'__version__ = "{os.environ["VERSION"]}"',
-                                 path.read_text(), flags=re.M))
-          PY
-
-      - name: Build
-        run: ./packaging/build-${{ matrix.kind }}.sh
-
-      - uses: actions/upload-artifact@v4
-        with:
-          name: dikte-${{ matrix.os }}
-          path: dist/*
-          if-no-files-found: error
+    uses: ./.github/workflows/build.yml
+    with:
+      ref: ${{ needs.version.outputs.ref }}
+      version: ${{ needs.version.outputs.prerelease == 'true' && needs.version.outputs.version || '' }}
 
   publish:
     needs: [version, build]
@@ -207,6 +153,12 @@ jobs:
           Accessibility permissions, which macOS asks for the first time each is
           used. It asks again after an update, because an application signed with
           no certificate is one macOS has never seen before.
+
+          Windows: run the setup, which installs for your account alone and asks
+          for no administrator. It carries the ffmpeg recording needs and adds a
+          Start Menu entry, a `dikte` command and, unless you untick it, a start
+          at sign-in. It is not signed either, so SmartScreen offers only "Don't
+          run" until you press More info. Add/Remove Programs uninstalls it.
           EOF
           )