Media browser: recursive scan entire content/ tree, /-media/ URL prefix, editor change detection fix

- handleMediaList() now scans content/ recursively for all media files
- URLs use /-media/ prefix mapping directly to content/ (no special cases)
- index.php: added /-media/ route, kept /-assets/ for backward compat
- editor-toolbar.js: fixed editor.on('change') placement (was inside switchMode)
- content-edit.php and content-new.php: back-btn unsaved-changes detection
- Removed unused __editorCleanup global

README.en.md

@@ -30,7 +30,7 @@ A lightweight, file-based content management system built with PHP.
 
 ```
 codepress/
-├── engine/
+├── cms/                            # Core CMS engine
 │   ├── core/
 │   │   ├── class/
 │   │   │   ├── CodePressCMS.php    # Main CMS class
@@ -48,27 +48,27 @@ codepress/
 │       ├── markdown_content.mustache
 │       ├── php_content.mustache
 │       └── html_content.mustache
-├── admin-console/                  # Admin panel
+├── admin/                          # Admin panel
 │   ├── config/
 │   │   ├── app.php                # Admin configuration
 │   │   └── admin.json             # Users & security
 │   ├── src/
 │   │   └── AdminAuth.php          # Authentication service
 │   └── templates/                  # Admin templates
+├── cli/                            # CLI scripts & tests
+│   └── test/
 ├── public/                         # Web root
 │   ├── assets/
 │   │   ├── css/
 │   │   ├── js/
 │   │   └── favicon.svg
-│   ├── content/                    # Content files
-│   │   ├── nl.homepage.md          # Dutch homepage
-│   │   ├── en.homepage.md          # English homepage
-│   │   └── [lang].[page].md        # Multi-language pages
 │   ├── index.php                   # Website entry point
 │   └── admin.php                   # Admin entry point
+├── content/                        # Content files
+├── plugins/                        # CMS plugins
+├── docs/                           # Documentation
 ├── config.json                     # Configuration
-├── version.php                     # Version tracking
-└── README.md                       # This file
+└── README.md
 ```
 
 ## ⚙️ Configuration