chore: cleanup dead code

internal/tui/styles/icons.go

@@ -10,16 +10,3 @@ const (
 	SpinnerIcon  string = "⟳"
 	DocumentIcon string = "🖼"
 )
-
-// CircledDigit returns the Unicode circled digit/number for 0‑20.
-// out‑of‑range → "".
-func CircledDigit(n int) string {
-	switch {
-	case n == 0:
-		return "\u24EA" // ⓪
-	case 1 <= n && n <= 20:
-		return string(rune(0x2460 + n - 1)) // ①–⑳
-	default:
-		return ""
-	}
-}