Add HA Sync (XMLRPC config sync) endpoint (/api/v2/system/hasync) #843

<?php

namespace RESTAPI\Models;

require_once 'RESTAPI/autoloader.inc';

use RESTAPI\Core\Model;
use RESTAPI\Fields\StringField;

class Hasync extends Model {
    public function __construct(...$options) {
        parent::__construct(...$options);

        $this->config_path = 'hasync';
        $this->many = false;

        // Core fields
        $this->synchronizetoip  = new StringField(allow_null: true);
        $this->pfsyncpeerip     = new StringField(allow_null: true);
        $this->pfsyncinterface  = new StringField(allow_null: true);

        $this->username         = new StringField(allow_null: true);
        $this->password         = new StringField(allow_null: true, write_only: true);

        // on/off flags
        foreach ([
            'synchronizeusers',
            'synchronizeauthservers',
            'synchronizecerts',
            'synchronizerules',
            'synchronizeschedules',
            'synchronizealiases',
            'synchronizenat',
            'synchronizeipsec',
            'synchronizeopenvpn',
            'synchronizedhcpd',
            'synchronizedhcrelay',
            'synchronizedhcrelay6',
            'synchronizewol',
            'synchronizestaticroutes',
            'synchronizevirtualip',
            'synchronizetrafficshaper',
            'synchronizetrafficshaperlimiter',
            'synchronizednsforwarder',
            'synchronizecaptiveportal',
            'pfsyncenabled',
        ] as $flag) {
            $this->$flag = new StringField(allow_null: true);
        }
    }

    public function apply_update(): void {
        @require_once('filter.inc');

        // Apply sync settings + reload
        if (function_exists('filter_configure_sync')) {
            filter_configure_sync();
        }
        if (function_exists('filter_configure')) {
            filter_configure();
        }
    }
}

<?php

namespace RESTAPI\Endpoints;

require_once 'RESTAPI/autoloader.inc';

use RESTAPI\Core\Endpoint;

/**
 * HA Sync settings endpoint (singleton model)
 */
class HasyncEndpoint extends Endpoint {
    public function __construct() {
        $this->url = '/api/v2/system/hasync';
        $this->model_name = 'Hasync';
        $this->request_method_options = ['GET', 'PATCH'];

        parent::__construct();
    }
}