Add image compression and improve document edit UI

- Add Swift ImageCompression helper to enforce 200KB limit on iOS
- Update iOS views to use compression for all image uploads
- Fix iOS EditDocumentView to show success only after all uploads complete
- Add AsyncImage thumbnails to Android EditDocumentScreen
- Fix Android success message visibility with delay before state reset
- Add proper error handling for failed image uploads
- Add resetUpdateState on error for consistency

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

iosApp/iosApp/Task/CompleteTaskView.swift

@@ -314,7 +314,8 @@ struct CompleteTaskView: View {
 
         // If there are images, upload with images
         if !selectedImages.isEmpty {
-            let imageDataArray = selectedImages.compactMap { $0.jpegData(compressionQuality: 0.8) }
+            // Compress images to meet size requirements
+            let imageDataArray = ImageCompression.compressImages(selectedImages)
             let imageByteArrays = imageDataArray.map { KotlinByteArray(data: $0) }
             let fileNames = (0..<imageDataArray.count).map { "image_\($0).jpg" }