Favorite themes from the appearance button's right-click menu (#2445)

* feat(ui): favorite themes from the appearance button's context menu

Hovering a theme in Preferences > Interface shows a star; clicking it saves
the theme to interface.favoriteThemes (filled accent star once favorited).
Right-clicking the title-bar appearance button opens a menu with Appearance
Settings, then the favorite light themes and the favorite dark themes.

* Regenerate the scorecard for the favorite themes pref

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Co-authored-by: Brandon Thomas <echelon@gmail.com>

assets/icons/star-filled.svg

@@ -0,0 +1,13 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="currentColor"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="M11.525 2.295a.53.53 0 0 1 .95 0l2.31 4.679a2.123 2.123 0 0 0 1.595 1.16l5.166.756a.53.53 0 0 1 .294.904l-3.736 3.638a2.123 2.123 0 0 0-.611 1.878l.882 5.14a.53.53 0 0 1-.771.56l-4.618-2.428a2.122 2.122 0 0 0-1.973 0L6.396 21.01a.53.53 0 0 1-.77-.56l.881-5.139a2.122 2.122 0 0 0-.611-1.879L2.16 9.795a.53.53 0 0 1 .294-.906l5.165-.755a2.122 2.122 0 0 0 1.597-1.16z" />
+</svg>

assets/icons/star.svg

@@ -0,0 +1,13 @@
+<svg
+  xmlns="http://www.w3.org/2000/svg"
+  width="24"
+  height="24"
+  viewBox="0 0 24 24"
+  fill="none"
+  stroke="currentColor"
+  stroke-width="2"
+  stroke-linecap="round"
+  stroke-linejoin="round"
+>
+  <path d="M11.525 2.295a.53.53 0 0 1 .95 0l2.31 4.679a2.123 2.123 0 0 0 1.595 1.16l5.166.756a.53.53 0 0 1 .294.904l-3.736 3.638a2.123 2.123 0 0 0-.611 1.878l.882 5.14a.53.53 0 0 1-.771.56l-4.618-2.428a2.122 2.122 0 0 0-1.973 0L6.396 21.01a.53.53 0 0 1-.77-.56l.881-5.139a2.122 2.122 0 0 0-.611-1.879L2.16 9.795a.53.53 0 0 1 .294-.906l5.165-.755a2.122 2.122 0 0 0 1.597-1.16z" />
+</svg>