Update all guides (NL + EN) for CodePress 2.5.2 features

- Admin guide: RBAC roles, role-based dashboard, plugin types (content/system)
- CodePress developer guide: plugin types, admin plugin API, SCSS compilation, asset serving
- Theme developer guide: SCSS sole CSS source, css_compiled read-only, guide layout
- Content manager guide: layout selection from theme.json, plugin order in frontmatter
- Both NL and EN updated with identical structure
- 35 files updated

guide/en/theme-developer/layouts.md

@@ -1,5 +1,7 @@
 # Layouts
 
+Layouts define the page structure (left sidebar, full width, etc.). Layouts are defined in `theme.json` and chosen via frontmatter in content files.
+
 ## Choosing a layout in content
 
 ```markdown
@@ -14,14 +16,58 @@ Content...
 
 ## Layouts in theme.json
 
+Layouts are defined in the `template` mapping. The `config.default_template` is the fallback for pages without a `layout:` frontmatter or with an unknown layout:
+
 ```json
 {
-  "default_layout": "full_content",
-  "layouts": {
-    "full_content": "full_content.twig",
-    "left_sidebar": "left_sidebar.twig",
-    "right_sidebar": "right_sidebar.twig",
-    "custom1": "custom1.twig"
-  }
+    "config": {
+        "default_template": "full_content"
+    },
+    "template": {
+        "full_content": "full_content.twig",
+        "left_sidebar": "left_sidebar.twig",
+        "right_sidebar": "right_sidebar.twig",
+        "custom1": "custom1.twig",
+        "guide": "guide.twig"
+    }
 }
-```
+```
+
+## Layout template
+
+A layout template extends `base.twig` and fills the `content` block:
+
+```twig
+{% extends 'base.twig' %}
+
+{% block content %}
+<div class="container">
+    {{ content|raw }}
+</div>
+{% endblock %}
+```
+
+## Layouts with sidebar
+
+Layouts with a sidebar can show plugin content:
+
+```twig
+{% extends 'base.twig' %}
+
+{% block content %}
+<div class="row">
+    <main class="col-md-8">
+        {{ content|raw }}
+    </main>
+    <aside class="col-md-4">
+        {{ sidebar_content|raw }}
+    </aside>
+</div>
+{% endblock %}
+```
+
+If a page has no plugins or the layout has no sidebar, `sidebar_content` is empty.
+
+## Guide layout
+
+The `guide` layout (`guide.twig`) is special for guides. It injects the Navigation plugin into the sidebar for sidebar navigation. Automatically used for pages in the `guide/` folder.