Merge branch 8.1.2 into main

[vladimir-litvinchik]

PR overview

This PR fixes printing in image mode, adds new option to control UI behavior when scrolling pages, improves performance when rendering to images and makes UI more portable by using own fonts instead of loading fonts from web.

🛠️ Changes

1️⃣ Fixed Printing in Image Mode

Several issues related to printing in image mode were reported on our Free Support Forum in this topic and have been fixed in this release.

Issue 1: Broken print functionality — open a file, select different pages, and click Print — nothing happens.
Issue 2: Page numbers in the print dialog no longer updated as before.

Both issues are now resolved.
The following image shows the printing process:

2️⃣ Added Option to Disable Page Scroll Animation

By default, there is a scroll animation when changing pages, as shown below:

To disable the animation and instantly navigate to a page, set EnableScrollAnimation to false:

builder.Services
   .AddGroupDocsViewerUI(config =>
   {
       config.EnableScrollAnimation = false;
   });

When the animation is disabled, page navigation behaves as follows:

3️⃣ Turned Off Thumbnail Creation in Image Mode

Thumbnails are only required when rendering to HTML with embedded or external resources.
When rendering to JPG or PNG, the actual page image is now used as a thumbnail to improve performance.

4️⃣ Use Only Local Fonts

The previous version used web fonts instead of local ones, which led to one of the issues reported in #75.

This issue has been fixed by using only local fonts.