style(minimal): remove emoji from share button

Remove emoji icon from the share button in minimal theme for cleaner UI.

Author: Sora4431

apps/web/src/lib/themes/minimal/ItineraryView.svelte

@@ -171,7 +171,7 @@
         class="minimal-share-btn"
         title="URLをコピー"
       >
-        🔗 共有
+        共有
       </button>
       <select
         value={itinerary.theme_id}