add utils script for checking if tools are installed

scripts/utils.sh

@@ -0,0 +1,26 @@
+#!/bin/bash
+# Common utility functions for shell scripts
+
+# Checks if a tool is installed and available in PATH.
+# Usage: is_tool_installed <tool_name>
+# Returns 0 if found, 1 otherwise.
+is_tool_installed() {
+    command -v "$1" &> /dev/null
+}
+
+# Ensures a tool is installed. Exits with an error if not.
+# Usage: ensure_tool_installed <tool_name> [optional_purpose_message]
+# Example: ensure_tool_installed curl "to download files"
+ensure_tool_installed() {
+    local tool_name="$1"
+    local purpose_message="$2"
+
+    if ! is_tool_installed "${tool_name}"; then
+        echo "Error: Required tool '${tool_name}' could not be found." >&2
+        if [ -n "${purpose_message}" ]; then
+            echo "       It is needed ${purpose_message}." >&2
+        fi
+        echo "       Please install it first and ensure it is in your PATH." >&2
+        exit 1
+    fi
+}