CMS 2.0 - Theme engine, logging, admin improvements

Major changes:
- New ThemeManager with Twig templating and SCSS compilation
- Dynamic themes system (themes/default, themes/demo)
- LogManager with SQLite storage and syslog forwarding
- RequestLogger with static helper methods
- Admin UI overhaul (Bootstrap 5, dark mode)
- Admin config page with logging and theme settings
- Admin logs page with filters and search
- Removed legacy Mustache templates
- Removed test plugin and theme
- Composer dependencies: Twig, scssphp, CommonMark, MaxMind GeoIP

vendor/maxmind-db/reader/ext/tests/001-load.phpt

@@ -0,0 +1,12 @@
+--TEST--
+Check for maxminddb presence
+--SKIPIF--
+<?php if (!extension_loaded('maxminddb')) {
+    echo 'skip';
+} ?>
+--FILE--
+<?php
+echo 'maxminddb extension is available';
+?>
+--EXPECT--
+maxminddb extension is available