Rename Project concept to Novel across the stack

Renames the domain concept from Project to Novel throughout the backend
(entities, DTOs, services, endpoints, ProjectAccessService/Permission,
ProjectId foreign keys), MCP server (tool names and routes), and the
React/Vite frontend (types, hooks, routes, components). Adds a new EF
Core migration (RenameProjectToNovel) using RenameTable/RenameColumn to
preserve existing data instead of dropping/recreating tables. Updates
CLAUDE.md's structure section to reference Novels/ instead of Projects/.

src/Novelly.Api/Program.cs

@@ -10,7 +10,7 @@ using Novelly.Api.Common;
 using Novelly.Api.Data;
 using Novelly.Api.Genres;
 using Novelly.Api.Imports;
-using Novelly.Api.Projects;
+using Novelly.Api.Novels;
 using Novelly.Api.Questions;
 using Novelly.Api.Tags;
 using Novelly.Api.Users;
@@ -88,9 +88,9 @@ app.MapDefaultEndpoints();
 app.MapGet("/api/health", () => Results.Ok(new { status = "ok" })).WithTags("Health").AllowAnonymous();
 
 app.MapUserEndpoints();
-app.MapProjectMemberEndpoints();
+app.MapNovelMemberEndpoints();
 
-app.MapProjectEndpoints()
+app.MapNovelEndpoints()
    .MapCharacterEndpoints()
    .MapChapterEndpoints()
    .MapBeatEndpoints()