feat(pdf-tools): add linearize pdf tool for web optimization

Add new linearize PDF tool that optimizes PDFs for fast web viewing using qpdf-wasm. Includes UI components, logic implementation, and test updates. The tool processes multiple PDFs and downloads them in a ZIP archive.

src/js/config/pdf-tools.ts

@@ -60,4 +60,5 @@ export const multiFileTools = [
   'heic-to-pdf',
   'tiff-to-pdf',
   'alternate-merge',
+  'linearize',
 ];