Add portable shell launcher

scripts/start.sh

@@ -0,0 +1,38 @@
+#!/usr/bin/env sh
+set -eu
+
+SCRIPT_DIR=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)
+APP_HOME=$(dirname -- "$SCRIPT_DIR")
+
+JAR_PATH=""
+for candidate in "$APP_HOME"/target/workutils-*.jar; do
+    if [ -f "$candidate" ] && [ "${candidate%-plain.jar}" = "$candidate" ]; then
+        JAR_PATH=$candidate
+        break
+    fi
+done
+
+if [ -z "$JAR_PATH" ]; then
+    echo "[ERROR] WorkUtils JAR not found under $APP_HOME/target" >&2
+    exit 1
+fi
+
+if ! command -v java >/dev/null 2>&1; then
+    echo "[ERROR] Java is not available. WorkUtils requires Java 17+." >&2
+    exit 1
+fi
+
+JAVA_VERSION=$(java -version 2>&1 | awk -F '"' '/version/ { print $2; exit }')
+JAVA_MAJOR=$(printf '%s\n' "$JAVA_VERSION" | awk -F. '{ if ($1 == 1) print $2; else print $1 }')
+case "$JAVA_MAJOR" in
+    ''|*[!0-9]*)
+        echo "[ERROR] Unable to determine Java version: $JAVA_VERSION" >&2
+        exit 1
+        ;;
+esac
+if [ "$JAVA_MAJOR" -lt 17 ]; then
+    echo "[ERROR] Java $JAVA_VERSION found. WorkUtils requires Java 17+." >&2
+    exit 1
+fi
+
+exec java -Dfile.encoding=UTF-8 "-Dworkutils.home=$APP_HOME" -jar "$JAR_PATH" "$@"