feat: ship an Inno Setup installer from the windows release job

windows/carrier.iss

@@ -0,0 +1,42 @@
+; carrier Windows installer. Packs the same portable bundle windows/
+; bundle.sh produces (dist/) into a classic setup.exe: Program Files,
+; Start Menu shortcut, optional desktop icon, Apps & Features uninstall
+; entry. Built by windows/installer.sh, which passes /DVersion= from
+; Cargo.toml.
+;
+; Not yet wired into the forgejo release job - deliberately local until
+; the experience is signed off.
+
+#ifndef Version
+  #error Pass the version: ISCC /DVersion=0.2.0 windows/carrier.iss
+#endif
+
+[Setup]
+AppId={{345BADA4-146B-4F57-B7D3-E9FD5D664F4B}
+AppName=carrier
+AppVersion={#Version}
+AppPublisher=randogoth
+DefaultDirName={autopf}\carrier
+DefaultGroupName=carrier
+; Next to the portable zip (paths relative to this script's directory).
+OutputDir=..
+OutputBaseFilename=carrier-windows-{#Version}-setup
+Compression=lzma2/max
+SolidCompression=yes
+WizardStyle=modern
+ArchitecturesInstallIn64BitMode=x64compatible
+UninstallDisplayName=carrier
+
+[Tasks]
+Name: "desktopicon"; Description: "Create a &desktop icon"; GroupDescription: "Additional icons:"
+
+[Files]
+Source: "..\dist\*"; DestDir: "{app}"; Flags: recursesubdirs createallsubdirs ignoreversion
+
+[Icons]
+; Shortcut icons come from carrier.exe's embedded .ico resource.
+Name: "{group}\carrier"; Filename: "{app}\carrier.exe"
+Name: "{autodesktop}\carrier"; Filename: "{app}\carrier.exe"; Tasks: desktopicon
+
+[Run]
+Filename: "{app}\carrier.exe"; Description: "Launch carrier"; Flags: nowait postinstall skipifsilent

windows/installer.sh

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+#!/usr/bin/env bash
+# Pack the dist/ bundle into carrier-windows-<version>-setup.exe.
+#
+# Run from the carrier checkout after windows/bundle.sh has produced
+# dist/. Requires Inno Setup 7 (per-user install, which its own
+# installer's "just me" option produces).
+set -euo pipefail
+
+say() { printf '\n==> %s\n' "$*"; }
+die() { printf '\n!! %s\n' "$*" >&2; exit 1; }
+
+# MSYS2's login shells prune LOCALAPPDATA from the environment, so fall
+# back to cygpath (CSIDL 28 = local AppData of the current user).
+if [ -n "${LOCALAPPDATA:-}" ]; then
+    appdata=$(cygpath -u "$LOCALAPPDATA")
+else
+    appdata=$(cygpath -F 28)
+fi
+ISCC="$appdata/Programs/Inno Setup 7/ISCC.exe"
+[ -f "$ISCC" ] || die "Inno Setup not found at $ISCC — install it from https://jrsoftware.org/isdl.php"
+
+[ -d dist ] || die "no dist/ bundle — run windows/bundle.sh first"
+
+version=$(sed -n 's/^version = "\(.*\)"$/\1/p' Cargo.toml | head -1)
+
+say "compiling the installer"
+# MSYS2_ARG_CONV_EXCL stops MSYS2 mangling /DVersion into a path.
+MSYS2_ARG_CONV_EXCL="*" "$ISCC" /DVersion="$version" windows/carrier.iss \
+    || die "ISCC failed"
+
+say "done — carrier-windows-$version-setup.exe (in the checkout root)"