feat: enhance PDF tools with new features and UI improvements

- Added 'Extract Attachments' and 'Edit Attachments' functionalities to manage embedded files in PDFs.
- Introduced new splitting options: by bookmarks and by a specified number of pages (N times).
- Updated the user interface to include new options and improved layout for better usability.
- Enhanced the GitHub link display with dynamic star count retrieval.
- Bumped version to 1.4.0 and updated footer to reflect the new version.
- Refactored existing code for better maintainability and added new TypeScript definitions for the new features.

src/js/config/tools.ts

@@ -312,6 +312,24 @@ export const categories = [
         icon: 'paperclip',
         subtitle: 'Embed one or more files into your PDF.',
       },
+      {
+        id: 'extract-attachments',
+        name: 'Extract Attachments',
+        icon: 'download',
+        subtitle: 'Extract all embedded files from PDF(s) as a ZIP.',
+      },
+      {
+        id: 'edit-attachments',
+        name: 'Edit Attachments',
+        icon: 'file-edit',
+        subtitle: 'View, remove, or replace attachments in your PDF.',
+      },
+      {
+        href: '/src/pages/pdf-multi-tool.html',
+        name: 'PDF Multi Tool',
+        icon: 'layers',
+        subtitle: 'Full-featured PDF editor with page management.',
+      },
       {
         id: 'split',
         name: 'Split PDF',