[et] add nice_urls / client version to system info

Author: shish

.github/ISSUE_TEMPLATE/bug_report.md

@@ -7,11 +7,13 @@ about: Create a report to help us improve
 **Server Software**
 (You can get all these stats from `http://<your site>/system_info`)
 
- - Shimmie version:
+ - Shimmie version: [2.1.0, 2.13.0-dev-20260220-3406022, ...]
  - Install method: [Docker, Git, Zip, ...]
  - Server OS: [Windows 11, Debian, Arch, MacOS, ...]
  - Database: [mysql, postgres, ...]
  - Web server: [apache, nginx, ...]
+ - Theme: [default, danbooru2, ...]
+ - Nice URLs: [enabled, disabled]
 
 **Client Software (please complete the following information)**
  - Device: [e.g. iphone, windows desktop]
@@ -27,4 +29,3 @@ A clear and concise description of what you expected to happen.
 
 **What actually happened?**
 If applicable, add screenshots to help explain your problem.
-

ext/et/main.php

@@ -81,6 +81,7 @@ private function get_site_info(): array
                 'title' => $config->get(SetupConfig::TITLE),
                 'theme' => $config->get(SetupConfig::THEME),
                 'url'   => (string)(make_link("")->asAbsolute()),
+                'nice_urls' => Url::are_niceurls_enabled(),
             ],
             "versions" => [
                 'shimmie' => SysConfig::getVersion(),
@@ -89,6 +90,7 @@ private function get_site_info(): array
                 'db'      => $database->get_driver_id()->value . " " . $database->get_version(),
                 'os'      => php_uname(),
                 'server'  =>  $_SERVER["SERVER_SOFTWARE"] ?? 'unknown',
+                'client'  =>  $_SERVER["HTTP_USER_AGENT"] ?? 'unknown',
             ],
             "extensions" => [
                 "core" => $core_exts,