feat: Implement keyboard shortcuts system with UI management, add txt-to-pdf tests, and introduce a generic warning modal.

src/js/logic/pdf-multi-tool.ts

@@ -5,6 +5,7 @@ import JSZip from 'jszip';
 import Sortable from 'sortablejs';
 import { downloadFile } from '../utils/helpers';
 import { renderPagesProgressively, cleanupLazyRendering, renderPageToCanvas, createPlaceholder } from '../utils/render-utils';
+import { initializeGlobalShortcuts } from '../utils/shortcuts-init.js';
 
 pdfjsLib.GlobalWorkerOptions.workerSrc = new URL(
   'pdfjs-dist/build/pdf.worker.min.mjs',
@@ -147,6 +148,8 @@ function initializeTool() {
   console.log('PDF Multi Tool: Initializing...');
   createIcons({ icons });
 
+  initializeGlobalShortcuts();
+
   document.getElementById('close-tool-btn')?.addEventListener('click', () => {
     window.location.href = '/';
   });