Install psalm as dev, sync scripts updates

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

@@ -0,0 +1,47 @@
+<?php
+
+namespace LanguageServerProtocol;
+
+class MarkdownClientCapabilities
+{
+
+    /**
+     * The name of the parser.
+     *
+     * @var string
+     */
+    public $parser;
+
+    /**
+     * The version of the parser.
+     *
+     * @var string|null
+     */
+    public $version;
+
+    /**
+     * A list of HTML tags that the client allows / supports in
+     * Markdown.
+     *
+     * @since 3.17.0
+     *
+     * @var string[]|null
+     */
+    public $allowedTags;
+
+    /**
+     * @param string|null $parser
+     * @param string|null $version
+     * @param string[]|null $allowedTags
+     */
+    public function __construct(
+        string $parser = null,
+        string $version = null,
+        array $allowedTags = null
+    ) {
+        /** @psalm-suppress PossiblyNullPropertyAssignmentValue */
+        $this->parser = $parser;
+        $this->version = $version;
+        $this->allowedTags = $allowedTags;
+    }
+}