SpiderMonkey js185 arm64: darwin artifact install script

ShellScripts/Darwin/install_mozilla_js.sh

@@ -0,0 +1,51 @@
+#!/bin/bash
+# Install the SpiderMonkey js185 arm64-macOS static library for Oolite.
+# Darwin twin of ShellScripts/Linux/install_mozilla_js.sh: same parameter
+# contract ("system", "home", or "build"), same target layout.
+# Parameter one: "system", "home", or "build" (defaults to home).
+# Parameter two: escalate command (defaults to sudo for 'system').
+
+run_script() {
+    local script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &> /dev/null && pwd)
+
+    source "$script_dir/../Linux/dep_location_fn.sh"
+    local lib_subdir target escalate
+    dep_location lib_subdir target escalate "mozilla_js" $1 $2
+
+    local release_url="https://github.com/OoliteProject/mozillajs-macos/releases/download/0.0.1/mozjs-js185-macos-arm64.tar.gz"
+
+    echo "Installing Mozilla JS library (arm64, interpreter-only) to $target"
+    [[ -n "$escalate" ]] && echo "Using escalation: $escalate"
+
+    local temp_staging=$(mktemp -d)
+    trap 'rm -rf "$temp_staging"' EXIT
+
+    if ! curl -fL "$release_url" | tar -xz -C "$temp_staging"; then
+        echo "❌ Mozilla JS library download or extract failed!" >&2
+        return 1
+    fi
+
+    if ! [[ -d "$temp_staging/include" ]]; then
+        echo "❌ Mozilla JS library extract empty!" >&2
+        return 1
+    fi
+
+    if ! $escalate cp -R "$temp_staging/include/"* "$target/include/"; then
+        echo "❌ Mozilla JS library header install failed!" >&2
+        return 1
+    fi
+    mkdir -p "$target/$lib_subdir"
+    if ! $escalate cp -R "$temp_staging/lib/"* "$target/$lib_subdir/"; then
+        echo "❌ Mozilla JS library install failed!" >&2
+        return 1
+    fi
+
+    echo "✅ Installation complete."
+}
+
+run_script "$@"
+status=$?
+
+if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+    exit $status
+fi