Refactor Windows installer progress parsing to improve file name handling

- Updated the parsing logic in `parseWindowsInstallerProgress` to extract the file name from the copy file path, ensuring only the file name is displayed in progress messages.
- Enhanced readability by renaming the variable from `relativePath` to `fileName` and added logic to handle paths correctly.

src/desktop/winappupdate.js

@@ -45,7 +45,10 @@ const parseWindowsInstallerProgress = (output) => {
       const copyFile = line.match(/^installer:COPY_FILE:(\d+):(.*)$/)
       if (copyFile) {
         const fileBytes = Number.parseInt(copyFile[1], 10)
-        const relativePath = copyFile[2].trim()
+        var fileName = copyFile[2].trim()
+        if (fileName.includes('\\')) {
+          fileName = fileName.split('\\').pop()
+        }
 
         if (Number.isFinite(fileBytes)) {
           copiedBytes += fileBytes
@@ -57,8 +60,8 @@ const parseWindowsInstallerProgress = (output) => {
           }
         }
 
-        if (relativePath) {
-          message = `Copying ${relativePath} (${formatBytes(fileBytes)})`
+        if (fileName) {
+          message = `Copying ${fileName} (${formatBytes(fileBytes)})`
         }
       }
     } else if (