Build modified streamline images

The official image from streamline does not currently work for the arm64
platform. As a temporary measure, the source code and docker build scripts
have been lifted from the official images and are used to build locally.

Some additional modifications are made to reduce overall image size, these
are documented in docker/README.md

docker/streamline-src/vendor/dflydev/dot-access-data/src/Util.php

@@ -0,0 +1,78 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is a part of dflydev/dot-access-data.
+ *
+ * (c) Dragonfly Development Inc.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Dflydev\DotAccessData;
+
+class Util
+{
+    /**
+     * Test if array is an associative array
+     *
+     * Note that this function will return true if an array is empty. Meaning
+     * empty arrays will be treated as if they are associative arrays.
+     *
+     * @param array<mixed> $arr
+     *
+     * @return bool
+     *
+     * @psalm-pure
+     */
+    public static function isAssoc(array $arr): bool
+    {
+        return !count($arr) || count(array_filter(array_keys($arr), 'is_string')) == count($arr);
+    }
+
+    /**
+     * Merge contents from one associtative array to another
+     *
+     * @param mixed $to
+     * @param mixed $from
+     * @param DataInterface::PRESERVE|DataInterface::REPLACE|DataInterface::MERGE $mode
+     *
+     * @return mixed
+     *
+     * @psalm-pure
+     */
+    public static function mergeAssocArray($to, $from, int $mode = DataInterface::REPLACE)
+    {
+        if ($mode === DataInterface::MERGE && self::isList($to) && self::isList($from)) {
+            return array_merge($to, $from);
+        }
+
+        if (is_array($from) && is_array($to)) {
+            foreach ($from as $k => $v) {
+                if (!isset($to[$k])) {
+                    $to[$k] = $v;
+                } else {
+                    $to[$k] = self::mergeAssocArray($to[$k], $v, $mode);
+                }
+            }
+
+            return $to;
+        }
+
+        return $mode === DataInterface::PRESERVE ? $to : $from;
+    }
+
+    /**
+     * @param mixed $value
+     *
+     * @return bool
+     *
+     * @psalm-pure
+     */
+    private static function isList($value): bool
+    {
+        return is_array($value) && array_values($value) === $value;
+    }
+}