Add multi-file page support and improve documentation

Update README to explain multi-file page functionality Add example
content files demonstrating the feature Improve folder type detection
logic Implement new routing for page-type folders Add support for mixed
content types in single pages Update navigation and metadata handling
for multi-file pages Remove legacy frontpage.php in favor of multi-file
approach Improve file-based routing documentation Add examples of
different content types working together Update router to handle
multi-file content rendering Implement proper sorting of content files
Add best practices for multi-file content organization

README.md

@@ -19,7 +19,7 @@ A minimal, file-based PHP framework for publishing content that will work for de
 ### Creating Content
 
 1. Create a directory for your content in the document root
-2. Add a content file (.md, .php or .html)
+2. Add one or more content files (`.md`, `.php`, or `.html`)
 3. Optionally add `metadata.ini` for title, date, and summary
 4. Optionally add `cover.jpg|webp` for list view thumbnails
 
@@ -29,8 +29,12 @@ Content is immediately accessible at the URL matching the directory path.
 
 ```
 /content/
+  00-welcome.php
+  01-introduction.md
   about/
-    page.md
+    00-overview.md
+    01-philosophy.html
+    02-technology.php
   blog/
     2025-11-01-hello-world/
       article.md
@@ -38,6 +42,37 @@ Content is immediately accessible at the URL matching the directory path.
       metadata.ini
 ```
 
+### Multi-File Pages
+
+Any folder without subdirectories is a **page-type folder**. All `.md`, `.html`, and `.php` files in that folder render together as a single page in **alphanumerical order**.
+
+This allows you to:
+
+- Break long content into manageable sections
+- Mix file formats freely (Markdown, HTML, PHP)
+- Reorder sections by renaming files
+- Include dynamic PHP content alongside static content
+
+**Example:**
+
+```
+/content/
+  docs/
+    00-introduction.md
+    01-setup.md
+    02-advanced.html
+    03-examples.php
+```
+
+All four files render as one page at `/docs/`, in that order.
+
+### Folder Types
+
+FolderWeb automatically determines how to render folders:
+
+- **Page-type folder** (no subdirectories) → Renders all content files as a single page
+- **Article-type folder** (has subdirectories) → Shows list view with links to subdirectories
+
 ### Customization
 
 All customization lives in `custom/`:
@@ -53,10 +88,11 @@ Never modify files in `/app/default/`—always override them in `custom/`.
 
 The folder hierarchy dictates URL structure:
 
-- `/about/page.md` → `yoursite.com/about`
-- `/blog/2025-11-01-post/article.md` → `yoursite.com/blog/2025-11-01-post`
+- Root content files → `yoursite.com/`
+- `/about/` (with content files) → `yoursite.com/about/`
+- `/blog/2025-11-01-post/` (with content files) → `yoursite.com/blog/2025-11-01-post/`
 - Dates in folder names are automatically extracted and formatted
-- Directories with subdirectories automatically show list views
+- Content file names can be anything (not limited to `page.md` or `article.md`)
 
 ### Metadata