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/types/settings.ts

@@ -22,4 +22,5 @@ export interface AppSettings {
   boardSortOrder: BoardSortOrder;
   boardManualOrder: string[];
   lastNotificationCheck: string | null;
+  reduceMotion: boolean;
 }