add reduce motion toggle and bump to v1.0.1

Add in-app reduce motion setting under Settings > Appearance so users
can disable animations without changing their OS preference. Applies a
.reduce-motion CSS class to kill all CSS transitions/animations and
wraps the app in MotionConfig to globally disable Framer Motion springs,
layout animations, and enter/exit transitions. Setting persists to disk.

Also removes leftover default Square*.png icons and bumps version to
1.0.1.

src/index.css

@@ -200,3 +200,12 @@
     scroll-behavior: auto !important;
   }
 }
+
+.reduce-motion *,
+.reduce-motion *::before,
+.reduce-motion *::after {
+  animation-duration: 0.01ms !important;
+  animation-iteration-count: 1 !important;
+  transition-duration: 0.01ms !important;
+  scroll-behavior: auto !important;
+}