refactor: update nginx config for new structure

- Updated posterg.conf with new directory structure
- Document root: /var/www/posterg/public
- Explicitly deny access to: /src, /templates, /config, /storage, /tests, /scripts, /docs
- Added structure diagram in comments
- Updated deploy scripts security checks
- Replaced outdated posterg.conf.reference

All non-public directories outside webroot for security.
Defense-in-depth: explicit deny rules even though paths outside /public.

config/bootstrap.php

@@ -1,4 +1,5 @@
 <?php
+
 /**
  * Simple configuration for website
  */
@@ -24,7 +25,8 @@ if (php_sapi_name() === 'cli-server') {
 }
 
 // Simple helper function for including templates
-function include_template($name) {
+function include_template($name)
+{
     $path = APP_ROOT . '/templates/' . $name;
     if (file_exists($path)) {
         include $path;