Fix white screen issue when loading website and improve build performance of frontend

Addressed an issue causing intermittent white screens during the loading process due to an empty index.html file. The frontend build process creates an empty file and then writes to it afterward, leading to an empty file for a short period, which may result in a white screen.

Additionally, fixed an issue with the Application Insights bundle generation, which is also generated in two steps. If the web app is loaded with the first (smaller) file, it also results in a white screen.

The solution involves:

Looping until the index.html is found.
Extracting the Application Insights script path using a regex.
Loading the script from the Web Server and checking if it’s the larger file.

Additional updates:

Using rimraf as cross-platform rm -rf.
Mark images on the landing page for lazy loading to improve page load.
Improved web app development build performance.

Checklist

[x] I have added a Label to the pull-request
[x] I have added tests, and done manual regression tests
[x] I have updated the documentation, if necessary

platformplatform / PlatformPlatform

Fix white screen issue when loading website and improve build performance of frontend #523

Checklist

Quality Gate passed