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/nunomaduro/termwind/src/Terminal.php

@@ -0,0 +1,50 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Termwind;
+
+use Symfony\Component\Console\Terminal as ConsoleTerminal;
+
+/**
+ * @internal
+ */
+final class Terminal
+{
+    /**
+     * An instance of Symfony's console terminal.
+     */
+    private ConsoleTerminal $terminal;
+
+    /**
+     * Creates a new terminal instance.
+     */
+    public function __construct(ConsoleTerminal $terminal = null)
+    {
+        $this->terminal = $terminal ?? new ConsoleTerminal();
+    }
+
+    /**
+     * Gets the terminal width.
+     */
+    public function width(): int
+    {
+        return $this->terminal->getWidth();
+    }
+
+    /**
+     * Gets the terminal height.
+     */
+    public function height(): int
+    {
+        return $this->terminal->getHeight();
+    }
+
+    /**
+     * Clears the terminal screen.
+     */
+    public function clear(): void
+    {
+        Termwind::getRenderer()->write("\ec");
+    }
+}