Take terminal width into account in supershell

Sometimes if the progress lines are wider than the terminal width,
the supershell blank zone can expand indefinitely because be do not move
the cursor far enough up to properly re-fill the blank zone.

internal/util-logging/src/main/scala/sbt/internal/util/ConsoleAppender.scala

@@ -346,9 +346,11 @@ class ConsoleAppender private[ConsoleAppender] (
       out.println(s"$DeleteLine$l")
       if (progress.length > 0) {
         val pad = if (padding.get > 0) padding.decrementAndGet() else 0
+        val width = ConsoleAppender.terminalWidth
+        val len: Int = progress.foldLeft(progress.length)(_ + terminalLines(width)(_))
         deleteConsoleLines(blankZone + pad)
         progress.foreach(out.println)
-        out.print(cursorUp(blankZone + progress.length + padding.get))
+        out.print(cursorUp(blankZone + len + padding.get))
       }
     }
     out.flush()
@@ -370,18 +372,25 @@ class ConsoleAppender private[ConsoleAppender] (
       s"$DeleteLine  | => ${item.name} ${elapsed}s"
     }
 
+    val width = ConsoleAppender.terminalWidth
+    val extra: Int = info.foldLeft(0)(_ + terminalLines(width)(_))
     val previousLines = progressLines.getAndSet(info)
+    val prevExtra = previousLines.foldLeft(0)(_ + terminalLines(width)(_))
+
     val prevPadding = padding.get
-    val newPadding = math.max(0, previousLines.length + prevPadding - info.length)
+    val newPadding =
+      math.max(0, previousLines.length + prevExtra + prevPadding - info.length - extra)
     padding.set(newPadding)
 
     deleteConsoleLines(newPadding)
     deleteConsoleLines(blankZone)
     info.foreach(i => out.println(i))
 
-    out.print(cursorUp(blankZone + info.length + newPadding))
+    out.print(cursorUp(blankZone + info.length + newPadding + extra))
     out.flush()
   }
+  private def terminalLines(width: Int): String => Int =
+    (progressLine: String) => (progressLine.length - 1) / width
   private def deleteConsoleLines(n: Int): Unit = {
     (1 to n) foreach { _ =>
       out.println(DeleteLine)