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/admin-beheerder/dashboard.md

@@ -1,10 +1,32 @@
 # Dashboard
 
-The dashboard shows an overview of:
+The dashboard shows a **role-based overview** of the website. Which widgets are visible depends on the role of the logged-in user.
 
-- Views (30 days)
-- Unique visitors
+## Roles and widgets
+
+### Admin
+- Views (30 days) and unique visitors
 - Number of pages and folders
 - Active plugins
 - Recent activity
-- Quick actions
+- System information
+- Quick actions (new page, plugin, theme)
+
+### Content Manager
+- Number of pages and folders
+- Recent content changes
+- Quick actions (new page, folder)
+
+### BI Manager
+- Views (30 days) and unique visitors
+- Top pages
+- Recent visits
+
+### Site Admin
+- Active plugins and themes
+- System information
+- Quick actions (theme, plugin, update)
+
+## Access
+
+The dashboard is the default page after login (`/admin/dashboard`). All roles have access to the dashboard.