Feature request: Add emoji support in labels #674

Describe the feature idea
It would be great if labels on buttons could include emoji.
Right now labels are plain text only, so things like a "Mute 🔇" button, a "Next track ⏭️" action, or a quick visual marker such as ✅ / ⚠️ have to be spelled out in words.
Allowing emoji in the label field would make decks more readable at a glance and let people add simple visual cues without needing custom icon images (they only work for the background anyway).

Additional context
Running version 1.5.0-beta.16 devel and it shows a empty square if a label has a emoji.