Install psalm as dev, sync scripts updates

vendor/felixfbecker/language-server-protocol/src/FileEvent.php

@@ -0,0 +1,33 @@
+<?php
+
+namespace LanguageServerProtocol;
+
+/**
+ * An event describing a file change.
+ */
+class FileEvent
+{
+    /**
+     * The file's URI.
+     *
+     * @var string
+     */
+    public $uri;
+
+    /**
+     * The change type.
+     *
+     * @var int
+     */
+    public $type;
+
+    /**
+     * @param string $uri
+     * @param int $type
+     */
+    public function __construct(string $uri, int $type)
+    {
+        $this->uri = $uri;
+        $this->type = $type;
+    }
+}