Performance: push ORDER BY/TAKE into SQL for hot-path reads

- IInAppNotificationRepository: typed repo with GetPagedAsync, GetRecentAsync, GetUnreadAsync
  — bell dropdown no longer loads all notifications then slices in C#
- Add compound indexes on InAppNotifications(CompanyId, IsDeleted, CreatedAt) and
  (CompanyId, IsDeleted, IsRead); ContactSubmissions(CompanyId, IsDeleted, CreatedAt)
- PlainRepository.GetAllAsync/FindAsync: add AsNoTracking (Announcements, Tips, ReleaseNotes)
- AiUsageReportController: replace GetAllAsync + C# Where with FindAsync (SQL-level filter)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/PowderCoating.Infrastructure/Data/ApplicationDbContext.cs

@@ -1031,6 +1031,17 @@ modelBuilder.Entity<ReworkRecord>().HasQueryFilter(e =>
         modelBuilder.Entity<AuditLog>()
             .HasIndex(a => new { a.EntityType, a.EntityId });
 
+        // InAppNotification — bell endpoint fires on every page load; compound indexes let SQL
+        // evaluate the tenant + soft-delete filter then sort/count without a full-table scan.
+        modelBuilder.Entity<InAppNotification>()
+            .HasIndex(n => new { n.CompanyId, n.IsDeleted, n.CreatedAt });
+        modelBuilder.Entity<InAppNotification>()
+            .HasIndex(n => new { n.CompanyId, n.IsDeleted, n.IsRead });
+
+        // ContactSubmission — SuperAdmin inbox; filter + sort covered by a single index.
+        modelBuilder.Entity<ContactSubmission>()
+            .HasIndex(c => new { c.CompanyId, c.IsDeleted, c.CreatedAt });
+
         // Announcements — no tenant filter; visible based on Target logic in app layer
         modelBuilder.Entity<AnnouncementDismissal>()
             .HasOne(d => d.Announcement)

src/PowderCoating.Infrastructure/Migrations/20260614012148_AddNotificationAndContactIndexes.cs

@@ -0,0 +1,88 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace PowderCoating.Infrastructure.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddNotificationAndContactIndexes : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.UpdateData(
+                table: "PricingTiers",
+                keyColumn: "Id",
+                keyValue: 1,
+                column: "CreatedAt",
+                value: new DateTime(2026, 6, 14, 1, 21, 46, 131, DateTimeKind.Utc).AddTicks(4191));
+
+            migrationBuilder.UpdateData(
+                table: "PricingTiers",
+                keyColumn: "Id",
+                keyValue: 2,
+                column: "CreatedAt",
+                value: new DateTime(2026, 6, 14, 1, 21, 46, 131, DateTimeKind.Utc).AddTicks(4196));
+
+            migrationBuilder.UpdateData(
+                table: "PricingTiers",
+                keyColumn: "Id",
+                keyValue: 3,
+                column: "CreatedAt",
+                value: new DateTime(2026, 6, 14, 1, 21, 46, 131, DateTimeKind.Utc).AddTicks(4197));
+
+            migrationBuilder.CreateIndex(
+                name: "IX_InAppNotifications_CompanyId_IsDeleted_CreatedAt",
+                table: "InAppNotifications",
+                columns: new[] { "CompanyId", "IsDeleted", "CreatedAt" });
+
+            migrationBuilder.CreateIndex(
+                name: "IX_InAppNotifications_CompanyId_IsDeleted_IsRead",
+                table: "InAppNotifications",
+                columns: new[] { "CompanyId", "IsDeleted", "IsRead" });
+
+            migrationBuilder.CreateIndex(
+                name: "IX_ContactSubmissions_CompanyId_IsDeleted_CreatedAt",
+                table: "ContactSubmissions",
+                columns: new[] { "CompanyId", "IsDeleted", "CreatedAt" });
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropIndex(
+                name: "IX_InAppNotifications_CompanyId_IsDeleted_CreatedAt",
+                table: "InAppNotifications");
+
+            migrationBuilder.DropIndex(
+                name: "IX_InAppNotifications_CompanyId_IsDeleted_IsRead",
+                table: "InAppNotifications");
+
+            migrationBuilder.DropIndex(
+                name: "IX_ContactSubmissions_CompanyId_IsDeleted_CreatedAt",
+                table: "ContactSubmissions");
+
+            migrationBuilder.UpdateData(
+                table: "PricingTiers",
+                keyColumn: "Id",
+                keyValue: 1,
+                column: "CreatedAt",
+                value: new DateTime(2026, 6, 10, 16, 17, 57, 120, DateTimeKind.Utc).AddTicks(9129));
+
+            migrationBuilder.UpdateData(
+                table: "PricingTiers",
+                keyColumn: "Id",
+                keyValue: 2,
+                column: "CreatedAt",
+                value: new DateTime(2026, 6, 10, 16, 17, 57, 120, DateTimeKind.Utc).AddTicks(9137));
+
+            migrationBuilder.UpdateData(
+                table: "PricingTiers",
+                keyColumn: "Id",
+                keyValue: 3,
+                column: "CreatedAt",
+                value: new DateTime(2026, 6, 10, 16, 17, 57, 120, DateTimeKind.Utc).AddTicks(9138));
+        }
+    }
+}

src/PowderCoating.Infrastructure/Migrations/ApplicationDbContextModelSnapshot.cs

@@ -2514,6 +2514,8 @@ namespace PowderCoating.Infrastructure.Migrations
 
                     b.HasKey("Id");
 
+                    b.HasIndex("CompanyId", "IsDeleted", "CreatedAt");
+
                     b.ToTable("ContactSubmissions");
                 });
 
@@ -3990,6 +3992,10 @@ namespace PowderCoating.Infrastructure.Migrations
 
                     b.HasIndex("QuoteId");
 
+                    b.HasIndex("CompanyId", "IsDeleted", "CreatedAt");
+
+                    b.HasIndex("CompanyId", "IsDeleted", "IsRead");
+
                     b.ToTable("InAppNotifications");
                 });
 
@@ -7204,7 +7210,7 @@ namespace PowderCoating.Infrastructure.Migrations
                         {
                             Id = 1,
                             CompanyId = 0,
-                            CreatedAt = new DateTime(2026, 6, 10, 16, 17, 57, 120, DateTimeKind.Utc).AddTicks(9129),
+                            CreatedAt = new DateTime(2026, 6, 14, 1, 21, 46, 131, DateTimeKind.Utc).AddTicks(4191),
                             Description = "Standard pricing for regular customers",
                             DiscountPercent = 0m,
                             IsActive = true,
@@ -7215,7 +7221,7 @@ namespace PowderCoating.Infrastructure.Migrations
                         {
                             Id = 2,
                             CompanyId = 0,
-                            CreatedAt = new DateTime(2026, 6, 10, 16, 17, 57, 120, DateTimeKind.Utc).AddTicks(9137),
+                            CreatedAt = new DateTime(2026, 6, 14, 1, 21, 46, 131, DateTimeKind.Utc).AddTicks(4196),
                             Description = "5% discount for preferred customers",
                             DiscountPercent = 5m,
                             IsActive = true,
@@ -7226,7 +7232,7 @@ namespace PowderCoating.Infrastructure.Migrations
                         {
                             Id = 3,
                             CompanyId = 0,
-                            CreatedAt = new DateTime(2026, 6, 10, 16, 17, 57, 120, DateTimeKind.Utc).AddTicks(9138),
+                            CreatedAt = new DateTime(2026, 6, 14, 1, 21, 46, 131, DateTimeKind.Utc).AddTicks(4197),
                             Description = "10% discount for premium customers",
                             DiscountPercent = 10m,
                             IsActive = true,

src/PowderCoating.Infrastructure/Repositories/InAppNotificationRepository.cs

@@ -0,0 +1,83 @@
+using Microsoft.EntityFrameworkCore;
+using PowderCoating.Core.Entities;
+using PowderCoating.Core.Interfaces.Repositories;
+using PowderCoating.Infrastructure.Data;
+
+namespace PowderCoating.Infrastructure.Repositories;
+
+/// <summary>
+/// Typed repository for <see cref="InAppNotification"/>. Overrides the three hot-path
+/// read operations so ORDER BY / SKIP / TAKE run in SQL rather than in C# after a full
+/// table load — critical for the bell dropdown (Recent/Unread) which fires on every page.
+/// </summary>
+public class InAppNotificationRepository
+    : Repository<InAppNotification>, IInAppNotificationRepository
+{
+    public InAppNotificationRepository(ApplicationDbContext context) : base(context) { }
+
+    /// <inheritdoc/>
+    public async Task<(List<InAppNotification> Items, int TotalCount)> GetPagedAsync(
+        bool isPlatformAdmin, int pageNumber, int pageSize)
+    {
+        // SuperAdmin path: bypass global filters, scope to CompanyId 0 (platform-only).
+        // Regular path: global filter already scopes to the current tenant.
+        var query = isPlatformAdmin
+            ? _context.Set<InAppNotification>()
+                .IgnoreQueryFilters()
+                .Where(n => !n.IsDeleted && n.CompanyId == 0)
+            : _context.Set<InAppNotification>()
+                .Where(n => true);
+
+        var totalCount = await query.CountAsync();
+
+        var items = await query
+            .AsNoTracking()
+            .OrderByDescending(n => n.CreatedAt)
+            .Skip((pageNumber - 1) * pageSize)
+            .Take(pageSize)
+            .ToListAsync();
+
+        return (items, totalCount);
+    }
+
+    /// <inheritdoc/>
+    public async Task<List<InAppNotification>> GetRecentAsync(
+        bool isPlatformAdmin, int take = 20)
+    {
+        var query = isPlatformAdmin
+            ? _context.Set<InAppNotification>()
+                .IgnoreQueryFilters()
+                .Where(n => !n.IsDeleted && n.CompanyId == 0)
+            : _context.Set<InAppNotification>()
+                .Where(n => true);
+
+        return await query
+            .AsNoTracking()
+            .OrderByDescending(n => n.CreatedAt)
+            .Take(take)
+            .ToListAsync();
+    }
+
+    /// <inheritdoc/>
+    public async Task<(List<InAppNotification> Items, int UnreadCount)> GetUnreadAsync(
+        bool isPlatformAdmin, int take = 20)
+    {
+        // Count ALL unread for the badge, then cap the items list for the dropdown.
+        var baseQuery = isPlatformAdmin
+            ? _context.Set<InAppNotification>()
+                .IgnoreQueryFilters()
+                .Where(n => !n.IsDeleted && n.CompanyId == 0 && !n.IsRead)
+            : _context.Set<InAppNotification>()
+                .Where(n => !n.IsRead);
+
+        var unreadCount = await baseQuery.CountAsync();
+
+        var items = await baseQuery
+            .AsNoTracking()
+            .OrderByDescending(n => n.CreatedAt)
+            .Take(take)
+            .ToListAsync();
+
+        return (items, unreadCount);
+    }
+}

src/PowderCoating.Infrastructure/Repositories/PlainRepository.cs

@@ -26,10 +26,10 @@ public class PlainRepository<T> : IPlainRepository<T> where T : class
         => await _dbSet.FindAsync(id);
 
     public virtual async Task<IEnumerable<T>> GetAllAsync()
-        => await _dbSet.ToListAsync();
+        => await _dbSet.AsNoTracking().ToListAsync();
 
     public virtual async Task<IEnumerable<T>> FindAsync(Expression<Func<T, bool>> predicate)
-        => await _dbSet.Where(predicate).ToListAsync();
+        => await _dbSet.AsNoTracking().Where(predicate).ToListAsync();
 
     public virtual async Task<T?> FirstOrDefaultAsync(Expression<Func<T, bool>> predicate)
         => await _dbSet.FirstOrDefaultAsync(predicate);

src/PowderCoating.Infrastructure/Repositories/UnitOfWork.cs

@@ -109,7 +109,7 @@ public class UnitOfWork : IUnitOfWork
     private IPlainRepository<Announcement>? _announcements;
     private IPlainRepository<BannedIp>? _bannedIps;
     private IPlainRepository<DashboardTip>? _dashboardTips;
-    private IRepository<InAppNotification>? _inAppNotifications;
+    private IInAppNotificationRepository? _inAppNotifications;
     private IPlainRepository<ReleaseNote>? _releaseNotes;
 
     // Bug Reports
@@ -439,8 +439,8 @@ public class UnitOfWork : IUnitOfWork
         _dashboardTips ??= new PlainRepository<DashboardTip>(_context);
 
     /// <summary>Repository for <see cref="InAppNotification"/> bell-notification records; tenant-filtered with soft delete.</summary>
-    public IRepository<InAppNotification> InAppNotifications =>
-        _inAppNotifications ??= new Repository<InAppNotification>(_context);
+    public IInAppNotificationRepository InAppNotifications =>
+        _inAppNotifications ??= new InAppNotificationRepository(_context);
 
     /// <summary>Repository for <see cref="ReleaseNote"/> platform changelog entries; no tenant filter, no soft delete.</summary>
     public IPlainRepository<ReleaseNote> ReleaseNotes =>