Add Length and Lines properties to Paragraph

* Adds Length and Lines to `Paragraph`, `Markup` and `Text`.
* Do not use Environment.NewLine

src/Spectre.Console/Widgets/Markup.cs

@@ -27,6 +27,16 @@ namespace Spectre.Console
             set => _paragraph.Overflow = value;
         }
 
+        /// <summary>
+        /// Gets the character count.
+        /// </summary>
+        public int Length => _paragraph.Length;
+
+        /// <summary>
+        /// Gets the number of lines.
+        /// </summary>
+        public int Lines => _paragraph.Lines;
+
         /// <summary>
         /// Initializes a new instance of the <see cref="Markup"/> class.
         /// </summary>

src/Spectre.Console/Widgets/Paragraph.cs

@@ -2,6 +2,7 @@ using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
+using System.Text;
 using Spectre.Console.Rendering;
 
 namespace Spectre.Console
@@ -25,6 +26,16 @@ namespace Spectre.Console
         /// </summary>
         public Overflow? Overflow { get; set; }
 
+        /// <summary>
+        /// Gets the character count of the paragraph.
+        /// </summary>
+        public int Length => _lines.Sum(line => line.Length) + Math.Max(0, Lines - 1);
+
+        /// <summary>
+        /// Gets the number of lines in the paragraph.
+        /// </summary>
+        public int Lines => _lines.Count;
+
         /// <summary>
         /// Initializes a new instance of the <see cref="Paragraph"/> class.
         /// </summary>

src/Spectre.Console/Widgets/Progress/Renderers/FallbackStatusRenderer.cs

@@ -29,7 +29,7 @@ namespace Spectre.Console
                     if (_lastStatus != task.Description)
                     {
                         _lastStatus = task.Description;
-                        _renderable = new Markup(task.Description + Environment.NewLine);
+                        _renderable = new Markup(task.Description + "\n");
                         return;
                     }
                 }

src/Spectre.Console/Widgets/Text.cs

@@ -47,6 +47,16 @@ namespace Spectre.Console
             set => _paragraph.Overflow = value;
         }
 
+        /// <summary>
+        /// Gets the character count.
+        /// </summary>
+        public int Length => _paragraph.Length;
+
+        /// <summary>
+        /// Gets the number of lines in the text.
+        /// </summary>
+        public int Lines => _paragraph.Lines;
+
         /// <inheritdoc/>
         protected override Measurement Measure(RenderContext context, int maxWidth)
         {