Stirling 2.0 (#3645)

# Description of Changes

Please provide a summary of the changes, including:

Vite fixes
Indexxdb

Closes #(issue_number)

---

## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md#6-testing)
for more details.

frontend/src/utils/thumbnailUtils.ts

@@ -0,0 +1,51 @@
+import { getDocument } from "pdfjs-dist";
+
+/**
+ * Generate thumbnail for a PDF file during upload
+ * Returns base64 data URL or undefined if generation fails
+ */
+export async function generateThumbnailForFile(file: File): Promise<string | undefined> {
+  // Skip thumbnail generation for large files to avoid memory issues
+  if (file.size >= 50 * 1024 * 1024) { // 50MB limit
+    console.log('Skipping thumbnail generation for large file:', file.name);
+    return undefined;
+  }
+  
+  try {
+    console.log('Generating thumbnail for', file.name);
+    
+    // Only read first 2MB for thumbnail generation to save memory
+    const chunkSize = 2 * 1024 * 1024; // 2MB
+    const chunk = file.slice(0, Math.min(chunkSize, file.size));
+    const arrayBuffer = await chunk.arrayBuffer();
+    
+    const pdf = await getDocument({ 
+      data: arrayBuffer,
+      disableAutoFetch: true,
+      disableStream: true
+    }).promise;
+    
+    const page = await pdf.getPage(1);
+    const viewport = page.getViewport({ scale: 0.2 }); // Smaller scale for memory efficiency
+    const canvas = document.createElement("canvas");
+    canvas.width = viewport.width;
+    canvas.height = viewport.height;
+    const context = canvas.getContext("2d");
+    
+    if (!context) {
+      throw new Error('Could not get canvas context');
+    }
+    
+    await page.render({ canvasContext: context, viewport }).promise;
+    const thumbnail = canvas.toDataURL();
+    
+    // Immediately clean up memory after thumbnail generation
+    pdf.destroy();
+    console.log('Thumbnail generated and PDF destroyed for', file.name);
+    
+    return thumbnail;
+  } catch (error) {
+    console.warn('Failed to generate thumbnail for', file.name, error);
+    return undefined;
+  }
+}