Add Xbox UWP build workflow

scripts/xbox-uwp/write_build_info.sh

@@ -0,0 +1,49 @@
+#!/usr/bin/env bash
+# Write provenance for an Xbox UWP package.
+#
+# Usage: scripts/xbox-uwp/write_build_info.sh OUTPUT VERSION CONFIGURATION
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+# shellcheck source=common.sh
+. "$SCRIPT_DIR/common.sh"
+
+OUTPUT="${1:-}"
+VERSION="${2:-}"
+CONFIGURATION="${3:-}"
+MANIFEST="$UWP_ROOT/third_party/manifest.json"
+
+[ -n "$OUTPUT" ] && [ -n "$VERSION" ] && [ -n "$CONFIGURATION" ] \
+  || fail "usage: $0 OUTPUT VERSION CONFIGURATION"
+[ -f "$MANIFEST" ] || fail "missing dependency manifest: $MANIFEST"
+
+mkdir -p "$(dirname "$OUTPUT")"
+GIT_COMMIT="$(git -C "$ROOT" rev-parse HEAD 2>/dev/null || echo unknown)"
+BUILT_AT="$(date -u +%Y-%m-%dT%H:%M:%SZ)"
+MANIFEST_SHA256="$(sha256_file "$MANIFEST")"
+LOVE_COMMIT="$(awk '
+  /"love"[[:space:]]*:/ { in_love=1 }
+  in_love && /"commit"[[:space:]]*:/ {
+    value=$0
+    sub(/^.*"commit"[[:space:]]*:[[:space:]]*"/, "", value)
+    sub(/".*$/, "", value)
+    print value
+    exit
+  }
+' "$MANIFEST")"
+[ -n "$LOVE_COMMIT" ] || fail "LÖVE revision is missing from the dependency manifest"
+
+cat > "$OUTPUT" <<EOF
+{
+  "platform": "xbox-uwp",
+  "version": "$VERSION",
+  "configuration": "$CONFIGURATION",
+  "gitCommit": "$GIT_COMMIT",
+  "loveCommit": "$LOVE_COMMIT",
+  "dependencyManifestSha256": "$MANIFEST_SHA256",
+  "builtAt": "$BUILT_AT"
+}
+EOF
+
+say "build info: $OUTPUT"