Add soft delete + trash, keyboard-first web overhaul, move chapter tags to bottom

Adds SoftDelete/Trash across characters, chapters, locations, beats with a
purge schedule and Trash page. Reworks the web client for keyboard-driven
navigation (focus helpers, help overlay, keyboard.md doc). Moves the
ChapterPage tag editor to the bottom of the page to match CharacterDetailPage.

src/Novelly.Api/Chapters/Chapter.cs

@@ -8,7 +8,7 @@ using Novelly.Api.Tags;
 
 namespace Novelly.Api.Chapters;
 
-public class Chapter
+public class Chapter : ISoftDeletable
 {
     public Guid Id { get; set; } = Guid.NewGuid();
     public Guid NovelId { get; set; }
@@ -33,6 +33,7 @@ public class Chapter
 
     public DateTimeOffset CreatedAt { get; set; } = DateTimeOffset.UtcNow;
     public DateTimeOffset UpdatedAt { get; set; } = DateTimeOffset.UtcNow;
+    public DateTimeOffset? DeletedAt { get; set; }
 
     public List<Beat> Beats { get; set; } = [];
 
@@ -48,5 +49,6 @@ public class ChapterEntityTypeConfiguration : IEntityTypeConfiguration<Chapter>
         entity.Property(c => c.Status).HasConversion<string>().HasMaxLength(32);
         entity.Property(c => c.Kind).HasConversion<string>().HasMaxLength(32);
         entity.HasIndex(c => new { c.NovelId, c.Number });
+        entity.HasQueryFilter(c => c.DeletedAt == null);
     }
 }

src/Novelly.Api/Chapters/ChapterContracts.cs

@@ -123,7 +123,7 @@ public static class ChapterMapping
 {
     public static ChapterResponse ToResponse(this Chapter c, int? displayNumber = null) => new(
         c.Id, c.NovelId, c.Number, c.Kind, displayNumber, c.Title, c.Summary,
-        [.. c.Locations.OrderBy(l => l.Name).Select(l => l.ToResponse())],
+        [.. c.Locations.Where(l => l.DeletedAt is null).OrderBy(l => l.Name).Select(l => l.ToResponse())],
         c.Notes,
         c.Status, c.TargetWordCount,
         [.. c.Beats.OrderBy(b => b.SortOrder).Select(b => b.ToResponse())],
@@ -133,7 +133,7 @@ public static class ChapterMapping
 
     public static ChapterSummaryResponse ToSummaryResponse(this Chapter c, int? displayNumber = null) => new(
         c.Id, c.NovelId, c.Number, c.Kind, displayNumber, c.Title, c.Summary,
-        [.. c.Locations.OrderBy(l => l.Name).Select(l => l.ToResponse())],
+        [.. c.Locations.Where(l => l.DeletedAt is null).OrderBy(l => l.Name).Select(l => l.ToResponse())],
         c.Status, c.TargetWordCount,
         c.Beats.Count, c.WordCount,
         [.. c.Tags.OrderBy(t => t.Name).Select(t => t.ToResponse())],

src/Novelly.Api/Chapters/ChapterEndpoints.cs

@@ -68,7 +68,7 @@ public static class ChapterEndpoints
 
         chapters.MapDelete("/{id:guid}", async (Guid id, ChapterService service, CancellationToken ct) =>
                 await service.DeleteAsync(id, ct) ? Results.NoContent() : Results.NotFound())
-            .WithSummary("Delete a chapter.");
+            .WithSummary("Move a chapter to the trash.");
 
         return app;
     }

src/Novelly.Api/Chapters/ChapterService.cs

@@ -31,7 +31,7 @@ public class ChapterService(
         return await db.Chapters
             .Include(c => c.Beats)
             .Include(c => c.Tags)
-            .Include(c => c.Locations)
+            .Include(c => c.Locations.Where(l => l.DeletedAt == null))
             .Where(c => c.NovelId == novelId)
             .OrderBy(c => c.Number)
             .ToListAsync(ct);
@@ -153,17 +153,18 @@ public class ChapterService(
     {
         Guard.Default(id, nameof(id));
 
-        logger.LogInformation("Deleting chapter {ChapterId}", id);
+        logger.LogInformation("Moving chapter {ChapterId} to trash", id);
 
-        var chapter = await FindAsync(id, ct);
+        var chapter = await db.Chapters.FirstOrDefaultAsync(c => c.Id == id, ct);
         if (chapter is null)
         {
+            logger.LogWarning("Chapter {ChapterId} not found", id);
             return false;
         }
 
         await access.RequireAsync(chapter.NovelId, NovelPermission.DeleteContent, ct);
 
-        db.Chapters.Remove(chapter);
+        chapter.DeletedAt = DateTimeOffset.UtcNow;
         activity.Record(chapter.NovelId, ActivityEntityKind.Chapter, ActivityAction.Deleted, chapter.Id, -chapter.WordCount);
         await db.SaveChangesAsync(ct);
         return true;
@@ -177,6 +178,7 @@ public class ChapterService(
         logger.LogDebug("Computing next chapter number for novel {NovelId}", novelId);
 
         var max = await db.Chapters
+            .IgnoreQueryFilters()
             .Where(c => c.NovelId == novelId)
             .MaxAsync(c => (int?)c.Number, ct);
 
@@ -190,10 +192,10 @@ public class ChapterService(
         logger.LogDebug("Finding chapter {ChapterId}", id);
 
         var chapter = await db.Chapters
-            .Include(c => c.Beats).ThenInclude(b => b.Characters)
+            .Include(c => c.Beats).ThenInclude(b => b.Characters.Where(ch => ch.DeletedAt == null))
             .Include(c => c.Beats).ThenInclude(b => b.Tags)
             .Include(c => c.Tags)
-            .Include(c => c.Locations)
+            .Include(c => c.Locations.Where(l => l.DeletedAt == null))
             .FirstOrDefaultAsync(c => c.Id == id, ct);
 
         if (chapter is null)