feat: Add subdirectory hosting support and fix asset path resolution

- Update README with comprehensive subdirectory hosting instructions and BASE_URL configuration guide
- Convert absolute asset paths to relative paths in index.html for proper subdirectory deployment
- Update all worker script imports to use relative paths instead of absolute paths
- Fix favicon and image references to work correctly when hosted in nested directories
- Normalize whitespace and formatting across worker files for consistency
- Update vite.config.ts to properly handle BASE_URL configuration for subdirectory deployments
- Ensure all tool pages and logic files maintain compatibility with subdirectory hosting
- Enable BentoPDF to be deployed at any URL path (e.g., example.com/tools/bentopdf/) without breaking asset loading

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

@@ -152,7 +152,7 @@ function initializeTool() {
   initializeGlobalShortcuts();
 
   document.getElementById('close-tool-btn')?.addEventListener('click', () => {
-    window.location.href = '/';
+    window.location.href = import.meta.env.BASE_URL;
   });
 
   document.getElementById('upload-pdfs-btn')?.addEventListener('click', () => {