refactor: rename Aternos\Mclogs to IndifferentKetchup\Iblogs

Bulk substitution across all PHP files in src/, build.php, worker.php,
and web/frontend/. Updates composer.json's package name and PSR-4
autoload root accordingly. Casing matches the existing
IndifferentKetchup\Codex package's namespace convention (capital K).

Strictly a namespace rename. Aternos\Codex\* imports remain in place;
those get re-pointed in a follow-up commit when the codex Composer
dependency itself is swapped. Filename renames (docker/mclogs.ini,
web/public/css/mclogs.css), README walk-through, env-var prefix changes,
and visible-text branding land in subsequent commits.

src/Api/Response/MultiResponse.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Aternos\Mclogs\Api\Response;
+namespace IndifferentKetchup\Iblogs\Api\Response;
 
 class MultiResponse extends ApiResponse
 {