Replace emarref/jwt with lcobucci/jwt

Refactor all JWT-related components
Replace RS256 with ES256 as a preferred JWT algorithm

api/components/Tokens/Algorithms/HS256.php

@@ -0,0 +1,50 @@
+<?php
+declare(strict_types=1);
+
+namespace api\components\Tokens\Algorithms;
+
+use Lcobucci\JWT\Signer;
+use Lcobucci\JWT\Signer\Hmac\Sha256;
+use Lcobucci\JWT\Signer\Key;
+
+class HS256 implements AlgorithmInterface {
+
+    /**
+     * @var string
+     */
+    private $key;
+
+    /**
+     * @var Key|null
+     */
+    private $loadedKey;
+
+    public function __construct(string $key) {
+        $this->key = $key;
+    }
+
+    public function getAlgorithmId(): string {
+        return 'HS256';
+    }
+
+    public function getSigner(): Signer {
+        return new Sha256();
+    }
+
+    public function getPrivateKey(): Key {
+        return $this->loadKey();
+    }
+
+    public function getPublicKey(): Key {
+        return $this->loadKey();
+    }
+
+    private function loadKey(): Key {
+        if ($this->loadedKey === null) {
+            $this->loadedKey = new Key($this->key);
+        }
+
+        return $this->loadedKey;
+    }
+
+}