Add outline import feature; drop Dto naming, map entities at the API boundary

Services now return entities; endpoints (and the agent toolsets) map to
*Response records instead of services building wire DTOs themselves.
Also brings in the outline-import agent, MCP tool, ledger and web dialog
that were already in progress on disk.

src/Novelly.Mcp/Tools/BeatTools.cs

@@ -36,7 +36,9 @@ public static class BeatTools
 
     [McpServerTool(Name = "update_beat")]
     [Description("Revise a beat. Only the fields you supply change. Supplying a tag list replaces "
-                 + "the beat's tags outright, so include the ones you want to keep.")]
+                 + "the beat's tags outright, so include the ones you want to keep. A character or "
+                 + "scene id already set stays put unless you pass clearCharacter/clearScene — "
+                 + "leaving the id null means 'don't touch it', not 'remove it'.")]
     public static Task<CallToolResult> UpdateBeat(
         NovelApiClient api,
         [Description("The beat's id.")] Guid beatId,
@@ -47,9 +49,11 @@ public static class BeatTools
         [Description("The event itself.")] string? whatHappened = null,
         [Description("What it sets in motion.")] string? whatsNext = null,
         [Description("Id of the scene this beat will be written into.")] Guid? sceneId = null,
-        [Description("Tags for cross-referencing. Replaces the existing tags.")] string[]? tags = null) =>
+        [Description("Tags for cross-referencing. Replaces the existing tags.")] string[]? tags = null,
+        [Description("Detach this beat's character, leaving it unassigned.")] bool clearCharacter = false,
+        [Description("Detach this beat's scene, leaving it ungrouped.")] bool clearScene = false) =>
         api.PatchAsync($"/api/beats/{beatId}",
-            new { title, sortOrder, characterId, whatHappened, whatsNext, sceneId, tags }, ct);
+            new { title, sortOrder, characterId, whatHappened, whatsNext, sceneId, tags, clearCharacter, clearScene }, ct);
 
     [McpServerTool(Name = "delete_beat")]
     [Description("Remove a beat from a chapter's outline. Confirm with the writer first.")]