Quick fixes for S&T (#27)

Some quick QAL changes I banged out this morning. The commit messages describe the individual changes in details.

## Changes

- Min window width on desktop.
- Removes white flash on desktop startup
- Removes right click menu on release builds (still exists on debug, and might come back in the future with new features).

Reviewed-on: #27
Reviewed-by: restitux <restitux@ohea.xyz>

gui/assets/main.scss

@@ -16,6 +16,7 @@ body {
 }
 
 #main {
+  visibility: visible;
   height: 100vh;
   display: flex;
   flex-direction: column;