Refactor PostgreSQL provider: multi-schema & async prep

- Refactor migrations and provider to use multiple PostgreSQL schemas, each matching a legacy SQLite database (activitylog, authentication, displaypreferences, library, users).
- All tables, foreign keys, and indexes are now schema-qualified; Down migration drops tables by schema.
- Provider ensures schemas exist before migrations; entities are mapped to correct schemas in OnModelCreating.
- Add support for max-pool-size, min-pool-size, and multiplexing connection options; update logging accordingly.
- VACUUM ANALYZE now runs per schema during scheduled optimization.
- TruncateAllTablesAsync now truncates tables with schema qualification.
- README updated with schema structure, new options, and multiplexing warnings.
- CacheDecorator now calls async repository methods using .GetAwaiter().GetResult(), with documentation.
- Lays groundwork for full async/await and multiplexing support in the database layer.

Jellyfin.Server.Implementations/Item/ChapterRepository.cs

@@ -36,16 +36,18 @@ public class ChapterRepository : IChapterRepository
     }
 
     /// <inheritdoc />
-    public ChapterInfo? GetChapter(Guid baseItemId, int index)
+    public async Task<ChapterInfo?> GetChapterAsync(Guid baseItemId, int index, CancellationToken cancellationToken = default)
     {
-        using var context = _dbProvider.CreateDbContext();
-        var chapter = context.Chapters.AsNoTracking()
+        await using var context = _dbProvider.CreateDbContext();
+        var chapter = await context.Chapters.AsNoTracking()
             .Select(e => new
             {
                 chapter = e,
                 baseItemPath = e.Item.Path
             })
-            .FirstOrDefault(e => e.chapter.ItemId.Equals(baseItemId) && e.chapter.ChapterIndex == index);
+            .FirstOrDefaultAsync(e => e.chapter.ItemId.Equals(baseItemId) && e.chapter.ChapterIndex == index, cancellationToken)
+            .ConfigureAwait(false);
+
         if (chapter is not null)
         {
             return Map(chapter.chapter, chapter.baseItemPath!);
@@ -55,36 +57,41 @@ public class ChapterRepository : IChapterRepository
     }
 
     /// <inheritdoc />
-    public IReadOnlyList<ChapterInfo> GetChapters(Guid baseItemId)
+    public async Task<IReadOnlyList<ChapterInfo>> GetChaptersAsync(Guid baseItemId, CancellationToken cancellationToken = default)
     {
-        using var context = _dbProvider.CreateDbContext();
-        return context.Chapters.AsNoTracking().Where(e => e.ItemId.Equals(baseItemId))
+        await using var context = _dbProvider.CreateDbContext();
+        var chapters = await context.Chapters.AsNoTracking()
+            .Where(e => e.ItemId.Equals(baseItemId))
             .Select(e => new
             {
                 chapter = e,
                 baseItemPath = e.Item.Path
             })
-            .AsEnumerable()
-            .Select(e => Map(e.chapter, e.baseItemPath!))
-            .ToArray();
+            .ToArrayAsync(cancellationToken)
+            .ConfigureAwait(false);
+
+        return chapters.Select(e => Map(e.chapter, e.baseItemPath!)).ToArray();
     }
 
     /// <inheritdoc />
-    public void SaveChapters(Guid itemId, IReadOnlyList<ChapterInfo> chapters)
+    public async Task SaveChaptersAsync(Guid itemId, IReadOnlyList<ChapterInfo> chapters, CancellationToken cancellationToken = default)
     {
-        using var context = _dbProvider.CreateDbContext();
-        using (var transaction = context.Database.BeginTransaction())
-        {
-            context.Chapters.Where(e => e.ItemId.Equals(itemId)).ExecuteDelete();
-            for (var i = 0; i < chapters.Count; i++)
-            {
-                var chapter = chapters[i];
-                context.Chapters.Add(Map(chapter, i, itemId));
-            }
+        await using var context = _dbProvider.CreateDbContext();
+        await using var transaction = await context.Database.BeginTransactionAsync(cancellationToken).ConfigureAwait(false);
 
-            context.SaveChanges();
-            transaction.Commit();
+        await context.Chapters
+            .Where(e => e.ItemId.Equals(itemId))
+            .ExecuteDeleteAsync(cancellationToken)
+            .ConfigureAwait(false);
+
+        for (var i = 0; i < chapters.Count; i++)
+        {
+            var chapter = chapters[i];
+            await context.Chapters.AddAsync(Map(chapter, i, itemId), cancellationToken).ConfigureAwait(false);
         }
+
+        await context.SaveChangesAsync(cancellationToken).ConfigureAwait(false);
+        await transaction.CommitAsync(cancellationToken).ConfigureAwait(false);
     }
 
     /// <inheritdoc />