tsu_financial_progress_block/tsu-financial-progress-block.php

<?php
/**
 * Plugin Name:       Tsu Financial Progress Block
 * Description:       Example block scaffolded with Create Block tool.
 * Requires at least: 6.1
 * Requires PHP:      7.0
 * Version:           0.1.0
 * Author:            The WordPress Contributors
 * License:           GPL-2.0-or-later
 * License URI:       https://www.gnu.org/licenses/gpl-2.0.html
 * Text Domain:       tsu-financial-progress-block
 *
 * @package           create-block
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit; // Exit if accessed directly.
}

// Register Custom Block Category
add_filter( 'block_categories_all',  function($categories) {
    
    // Set Category Slug
    $new_slug = 'tsu-category';
    // Set Category Title
    $new_title = 'To się uda';

    $has_category = false;

    foreach($categories as $category) {
        if($category === [ 'slug' => $new_slug, 'title' => $new_title]) {
            $has_category = true;
        }
    }
    if(!$has_category) {
        $categories[] = array(
            'slug' => $new_slug,
            'title' => $new_title
        );
    };
    
    return $categories;
});

/**
 * Registers the block using the metadata loaded from the `block.json` file.
 * Behind the scenes, it registers also all assets so they can be enqueued
 * through the block editor in the corresponding context.
 *
 * @see https://developer.wordpress.org/reference/functions/register_block_type/
 */
function tsu_financial_progress_block_tsu_financial_progress_block_block_init() {
	register_block_type( __DIR__ . '/build' );
}
add_action( 'init', 'tsu_financial_progress_block_tsu_financial_progress_block_block_init' );