Remove Scenes, group beats by multiple characters; strip comments repo-wide

Drop the Scene entity/grouping in favor of chapters carrying prose directly
and beats belonging to many characters. Add markdown editor + character
multi-select components to the web client. Remove all XML doc and inline
comments across the touched C#/TS/CSS files in favor of self-documenting
names, and record that convention in CLAUDE.md. Add .mcp.json (local MCP
server config, no secrets) and ignore .idea/.

src/Novelly.Api/Chapters/Chapter.cs

@@ -2,29 +2,22 @@ using Novelly.Api.Beats;
 using Novelly.Api.Characters;
 using Novelly.Api.Common;
 using Novelly.Api.Projects;
-using Novelly.Api.Scenes;
 using Novelly.Api.Tags;
 
 namespace Novelly.Api.Chapters;
 
-/// <summary>A chapter: an ordered container of scenes plus its own planning fields.</summary>
 public class Chapter
 {
     public Guid Id { get; set; } = Guid.NewGuid();
     public Guid ProjectId { get; set; }
     public Project? Project { get; set; }
 
-    /// <summary>Position in the manuscript, 1-based.</summary>
     public int Number { get; set; }
 
     public string Title { get; set; } = string.Empty;
 
-    /// <summary>
-    /// The paragraph that opens the chapter's outline, above the beat table.
-    /// </summary>
     public string? Summary { get; set; }
 
-    /// <summary>Whose head we are in for this chapter.</summary>
     public Guid? PovCharacterId { get; set; }
     public Character? PovCharacter { get; set; }
 
@@ -34,14 +27,14 @@ public class Chapter
     public DraftStatus Status { get; set; } = DraftStatus.Planned;
     public int? TargetWordCount { get; set; }
 
+    public string? Prose { get; set; }
+
+    public int WordCount { get; set; }
+
     public DateTimeOffset CreatedAt { get; set; } = DateTimeOffset.UtcNow;
     public DateTimeOffset UpdatedAt { get; set; } = DateTimeOffset.UtcNow;
 
-    /// <summary>The chapter's outline: an ordered, flat list of beats.</summary>
     public List<Beat> Beats { get; set; } = [];
 
-    /// <summary>The prose layer. Beats may optionally be grouped under these.</summary>
-    public List<Scene> Scenes { get; set; } = [];
-
     public List<Tag> Tags { get; set; } = [];
 }