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/.

.mcp.json

@@ -0,0 +1,11 @@
+{
+  "mcpServers": {
+    "novelly": {
+      "command": "/home/james/src/novelly/mcp-server/Novelly.Mcp",
+      "env": {
+        "NOVELLY_API_URL": "http://localhost:5080",
+        "DOTNET_ROOT": "/home/james/.dotnet"
+      }
+    }
+  }
+}