Blur Perfected 5.3.2-rev.2 for Minecraft 1.21.8

Blur Perfected has been archived. Blur Perfected will not receive any further updates unless the author decides to unarchive the project.

This update expands the functionality of Blur+ to be more consistent throughout the game, and more configurable.

Changes:

new feature that let's you select different animation curves for the background gradient and/or blur animations
fix blur slider not working past 10 (broken again by the upstream blur+ 5.3.2)
new feature that let's you toggle blur for Book edit/view/sign screen, Command Block edit screen and Sign edit screen separately, these screens were not previously blurred at all by the upstream blur+ 5.3.2
optimization for not drawing background gradient or blur animations when it's not noticeable
fix a bug where disabling gradient background would not disable it in some scenarios