feat(deploy): add PendingDeployment entity + migration

src/ZB.MOM.WW.ScadaBridge.Commons/Entities/Deployment/PendingDeployment.cs

@@ -0,0 +1,58 @@
+namespace ZB.MOM.WW.ScadaBridge.Commons.Entities.Deployment;
+
+/// <summary>
+/// A flattened instance config staged for a single in-flight deployment, fetched
+/// by the site over HTTP instead of being shipped inside an Akka message (avoids
+/// the 128 KB frame limit). Keyed by DeploymentId; at most one row per InstanceId
+/// (a newer deploy supersedes the prior pending row). Carries a per-deployment
+/// fetch token and a TTL. Promoted to DeployedConfigSnapshot on success; purged
+/// on failure/timeout/TTL.
+/// </summary>
+public class PendingDeployment
+{
+    /// <summary>Primary key.</summary>
+    public int Id { get; set; }
+
+    /// <summary>Unique deployment identifier assigned at deploy time; the fetch key for the staged config.</summary>
+    public string DeploymentId { get; set; }
+
+    /// <summary>Foreign key to the owning <c>Instance</c> entity. At most one pending row per instance.</summary>
+    public int InstanceId { get; set; }
+
+    /// <summary>Revision hash of the flattened configuration, used for staleness detection.</summary>
+    public string RevisionHash { get; set; }
+
+    /// <summary>JSON-serialized flattened configuration staged for the site to fetch.</summary>
+    public string ConfigurationJson { get; set; }
+
+    /// <summary>Per-deployment fetch token presented by the site to authorize the HTTP fetch.</summary>
+    public string Token { get; set; }
+
+    /// <summary>UTC timestamp when this pending row was created.</summary>
+    public DateTimeOffset CreatedAtUtc { get; set; }
+
+    /// <summary>UTC timestamp after which this pending row is considered expired (TTL) and may be purged.</summary>
+    public DateTimeOffset ExpiresAtUtc { get; set; }
+
+    /// <summary>Initializes a new pending deployment with its identity, staged configuration, fetch token, and TTL.</summary>
+    /// <param name="deploymentId">Unique deployment identifier (fetch key).</param>
+    /// <param name="instanceId">Owning instance identifier.</param>
+    /// <param name="revisionHash">Revision hash of the flattened configuration.</param>
+    /// <param name="configurationJson">JSON-serialized flattened configuration.</param>
+    /// <param name="token">Per-deployment fetch token.</param>
+    /// <param name="createdAtUtc">UTC creation timestamp.</param>
+    /// <param name="expiresAtUtc">UTC expiry timestamp (TTL).</param>
+    public PendingDeployment(
+        string deploymentId, int instanceId, string revisionHash,
+        string configurationJson, string token,
+        DateTimeOffset createdAtUtc, DateTimeOffset expiresAtUtc)
+    {
+        DeploymentId = deploymentId ?? throw new ArgumentNullException(nameof(deploymentId));
+        InstanceId = instanceId;
+        RevisionHash = revisionHash ?? throw new ArgumentNullException(nameof(revisionHash));
+        ConfigurationJson = configurationJson ?? throw new ArgumentNullException(nameof(configurationJson));
+        Token = token ?? throw new ArgumentNullException(nameof(token));
+        CreatedAtUtc = createdAtUtc;
+        ExpiresAtUtc = expiresAtUtc;
+    }
+}

src/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase/Configurations/PendingDeploymentConfiguration.cs

@@ -0,0 +1,28 @@
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Metadata.Builders;
+using ZB.MOM.WW.ScadaBridge.Commons.Entities.Deployment;
+using ZB.MOM.WW.ScadaBridge.Commons.Entities.Instances;
+
+namespace ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Configurations;
+
+public class PendingDeploymentConfiguration : IEntityTypeConfiguration<PendingDeployment>
+{
+    /// <summary>Configures the EF Core mapping for <see cref="PendingDeployment"/>.</summary>
+    /// <param name="builder">The entity type builder.</param>
+    public void Configure(EntityTypeBuilder<PendingDeployment> builder)
+    {
+        builder.ToTable("PendingDeployments");
+        builder.HasKey(x => x.Id);
+        builder.Property(x => x.DeploymentId).IsRequired().HasMaxLength(100);
+        builder.HasIndex(x => x.DeploymentId).IsUnique();
+        builder.HasIndex(x => x.InstanceId);
+        builder.HasIndex(x => x.ExpiresAtUtc);
+        builder.Property(x => x.RevisionHash).IsRequired().HasMaxLength(100);
+        builder.Property(x => x.ConfigurationJson).IsRequired();   // nvarchar(max)
+        builder.Property(x => x.Token).IsRequired().HasMaxLength(128);
+
+        builder.HasOne<Instance>().WithMany()
+               .HasForeignKey(x => x.InstanceId)
+               .OnDelete(DeleteBehavior.Cascade);
+    }
+}

src/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase/Migrations/20260626161432_AddPendingDeployment.cs

@@ -0,0 +1,63 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddPendingDeployment : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "PendingDeployments",
+                columns: table => new
+                {
+                    Id = table.Column<int>(type: "int", nullable: false)
+                        .Annotation("SqlServer:Identity", "1, 1"),
+                    DeploymentId = table.Column<string>(type: "nvarchar(100)", maxLength: 100, nullable: false),
+                    InstanceId = table.Column<int>(type: "int", nullable: false),
+                    RevisionHash = table.Column<string>(type: "nvarchar(100)", maxLength: 100, nullable: false),
+                    ConfigurationJson = table.Column<string>(type: "nvarchar(max)", nullable: false),
+                    Token = table.Column<string>(type: "nvarchar(128)", maxLength: 128, nullable: false),
+                    CreatedAtUtc = table.Column<DateTimeOffset>(type: "datetimeoffset", nullable: false),
+                    ExpiresAtUtc = table.Column<DateTimeOffset>(type: "datetimeoffset", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_PendingDeployments", x => x.Id);
+                    table.ForeignKey(
+                        name: "FK_PendingDeployments_Instances_InstanceId",
+                        column: x => x.InstanceId,
+                        principalTable: "Instances",
+                        principalColumn: "Id",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.CreateIndex(
+                name: "IX_PendingDeployments_DeploymentId",
+                table: "PendingDeployments",
+                column: "DeploymentId",
+                unique: true);
+
+            migrationBuilder.CreateIndex(
+                name: "IX_PendingDeployments_ExpiresAtUtc",
+                table: "PendingDeployments",
+                column: "ExpiresAtUtc");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_PendingDeployments_InstanceId",
+                table: "PendingDeployments",
+                column: "InstanceId");
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "PendingDeployments");
+        }
+    }
+}

src/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase/Migrations/ScadaBridgeDbContextModelSnapshot.cs

@@ -267,6 +267,54 @@ namespace ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Migrations
                     b.ToTable("DeploymentRecords");
                 });
 
+            modelBuilder.Entity("ZB.MOM.WW.ScadaBridge.Commons.Entities.Deployment.PendingDeployment", b =>
+                {
+                    b.Property<int>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("int");
+
+                    SqlServerPropertyBuilderExtensions.UseIdentityColumn(b.Property<int>("Id"));
+
+                    b.Property<string>("ConfigurationJson")
+                        .IsRequired()
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<DateTimeOffset>("CreatedAtUtc")
+                        .HasColumnType("datetimeoffset");
+
+                    b.Property<string>("DeploymentId")
+                        .IsRequired()
+                        .HasMaxLength(100)
+                        .HasColumnType("nvarchar(100)");
+
+                    b.Property<DateTimeOffset>("ExpiresAtUtc")
+                        .HasColumnType("datetimeoffset");
+
+                    b.Property<int>("InstanceId")
+                        .HasColumnType("int");
+
+                    b.Property<string>("RevisionHash")
+                        .IsRequired()
+                        .HasMaxLength(100)
+                        .HasColumnType("nvarchar(100)");
+
+                    b.Property<string>("Token")
+                        .IsRequired()
+                        .HasMaxLength(128)
+                        .HasColumnType("nvarchar(128)");
+
+                    b.HasKey("Id");
+
+                    b.HasIndex("DeploymentId")
+                        .IsUnique();
+
+                    b.HasIndex("ExpiresAtUtc");
+
+                    b.HasIndex("InstanceId");
+
+                    b.ToTable("PendingDeployments", (string)null);
+                });
+
             modelBuilder.Entity("ZB.MOM.WW.ScadaBridge.Commons.Entities.Deployment.SystemArtifactDeploymentRecord", b =>
                 {
                     b.Property<int>("Id")
@@ -1720,6 +1768,15 @@ namespace ZB.MOM.WW.ScadaBridge.ConfigurationDatabase.Migrations
                         .IsRequired();
                 });
 
+            modelBuilder.Entity("ZB.MOM.WW.ScadaBridge.Commons.Entities.Deployment.PendingDeployment", b =>
+                {
+                    b.HasOne("ZB.MOM.WW.ScadaBridge.Commons.Entities.Instances.Instance", null)
+                        .WithMany()
+                        .HasForeignKey("InstanceId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+                });
+
             modelBuilder.Entity("ZB.MOM.WW.ScadaBridge.Commons.Entities.ExternalSystems.ExternalSystemMethod", b =>
                 {
                     b.HasOne("ZB.MOM.WW.ScadaBridge.Commons.Entities.ExternalSystems.ExternalSystemDefinition", null)

src/ZB.MOM.WW.ScadaBridge.ConfigurationDatabase/ScadaBridgeDbContext.cs

@@ -89,6 +89,8 @@ public class ScadaBridgeDbContext : DbContext, IDataProtectionKeyContext
     public DbSet<SystemArtifactDeploymentRecord> SystemArtifactDeploymentRecords => Set<SystemArtifactDeploymentRecord>();
     /// <summary>Gets the set of deployed configuration snapshots.</summary>
     public DbSet<DeployedConfigSnapshot> DeployedConfigSnapshots => Set<DeployedConfigSnapshot>();
+    /// <summary>Gets the set of pending deployments staged for HTTP fetch by sites.</summary>
+    public DbSet<PendingDeployment> PendingDeployments => Set<PendingDeployment>();
 
     // External Systems
     /// <summary>Gets the set of external system definitions.</summary>