fix: index.php being directly usable in routing

Does not allow `/index.php` to be the basepath. This prevents having a duplicate
of each page:
- / !== /index.php/
- /some-route/example !== /index.php/some-route/example

Should make all search engine indexers a bit more happy.

module/Application/src/Router/LanguageAwareTreeRouteStack.php

@@ -152,6 +152,12 @@ public function match(
         // Store the original base URL (likely only just set above).
         $oldBaseUrl = $this->getBaseUrl();
 
+        // Do not allow direct access using /index.php. It is too difficult to properly configure this in NGINX, as we
+        // want to keep using the Laminas-generated 404 page and not a generic NGINX 404 page.
+        if (str_starts_with($oldBaseUrl, '/index.php')) {
+            return null;
+        }
+
         // Get the path from the URI, strip the base from it, and finally split it on `/`s.
         $uri = $request->getUri();
         $strippedPath = ltrim(