Add app icons for desktop

domain/src/commonMain/kotlin/ch/dissem/yaep/domain/generator.kt

@@ -65,20 +65,6 @@ internal fun solve(
         } catch (_: UnsolvablePuzzleException) {
             return NO_SOLUTION
         }
-        // TODO: this breaks stuff and is probably unnecessary, but further tests might be needed
-//        grid.forEach { row -> row.forEach { cell -> row.cleanupOptions(cell) } }
-//        grid.forEach { row ->
-//            row.filter { it.selection == null && it.options.size in 2..row.size / 2 }
-//                .groupBy { cell -> cell.options }
-//                .filter { it.value.size == it.key.size }
-//                .forEach { entry ->
-//                    val groupOptions = entry.key
-//                    val group = entry.value
-//                    println("removing options for group ${groupOptions.map { it.symbol }}")
-//                    row.filter { !group.contains(it) }
-//                        .forEach { it.options.removeAll(groupOptions) }
-//                }
-//        }
         grid.cleanupOptions()
     } while (removedOptions)