Release Jarl under the MIT License

LICENSE is installed with the docs, included in make dist, and becomes
the Debian package's copyright file together with the bundled Cinzel
font's OFL.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

scripts/mkdeb.sh

@@ -58,6 +58,24 @@ GOOS=linux GOARCH=$goarch GOARM=$goarm CGO_ENABLED=0 go build -ldflags "$LDFLAGS
 make --no-print-directory install-files DESTDIR="$root" PREFIX=/usr \
 	UNITDIR=/usr/lib/systemd/system JARLD_BIN="$work/jarld" JARL_BIN="$work/jarl" >/dev/null
 
+# Debian's machine-readable copyright file, from LICENSE and the bundled
+# font's licence (the font is embedded in jarld's web UI).
+indent() { sed -e 's/^$/./' -e 's/^/ /' "$1"; }
+{
+	echo "Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/"
+	echo "Upstream-Name: jarl"
+	echo
+	echo "Files: *"
+	echo "Copyright: $(sed -n 's/^Copyright (c) //p' LICENSE)"
+	echo "License: Expat"
+	indent LICENSE
+	echo
+	echo "Files: internal/web/static/assets/fonts/*"
+	echo "Copyright: 2020 The Cinzel Project Authors"
+	echo "License: OFL-1.1"
+	indent internal/web/static/assets/fonts/Cinzel-OFL.txt
+} > "$root/usr/share/doc/jarl/copyright"
+
 for f in postinst prerm postrm; do
 	install -m 0755 "deploy/debian/$f" "$root/DEBIAN/$f"
 done