[CLAUDE] Infra: Plan B Chunk A2 — Mig 32 Contract V2 schema + Configuration + Seed sample workflow

Cookie-cutter mirror PE Mig 23+24 GỘP thành 1 Mig 32 (ADD 2 column +
FK + IX). Mirror Mig 26 pattern cho FK Restrict.

Files added/modified:
- Migrations/20260522051059_AddApprovalWorkflowToContract.cs (3-file rule ✅)
- Migrations/20260522051059_AddApprovalWorkflowToContract.Designer.cs
- Migrations/ApplicationDbContextModelSnapshot.cs (updated)
- Configurations/ContractConfiguration.cs (+HasIndex + FK Restrict ApprovalWorkflows)
- Persistence/DbInitializer.cs (SeedSampleContractWorkflowV2 idempotent QT-HD-V2-001)

Mig 32 Up():
- ADD COLUMN Contracts.ApprovalWorkflowId Guid? NULL
- ADD COLUMN Contracts.CurrentApprovalLevelOrder int? NULL
- ADD INDEX IX_Contracts_ApprovalWorkflowId (filtered NOT NULL)
- ADD FK FK_Contracts_ApprovalWorkflows_ApprovalWorkflowId Restrict

Seed sample workflow (UAT smoke + admin Designer default):
- Code: QT-HD-V2-001 Name: "Quy trình duyệt HĐ mẫu UAT V2"
- ApplicableType: 3 (Contract) IsActive: true IsUserSelectable: true
- 1 Step "Bước 1 - Phòng CCM" + 1 Level + Approver Lê Văn Bình CCM
- Idempotent: skip nếu Code+Version existing

V1 coexist: 7 prod contract giữ WorkflowDefinitionId; V2 mới pin
ApprovalWorkflowId. Service ApproveV2Async (Chunk B em main) sẽ branch.

Verify (Implementer):
- dotnet build SolutionErp.slnx PASS 0 err (em main WIP stashed for verify)
- dotnet ef database update Dev PASS (Mig 32 applied)
- 3-file rule Mig: mig.cs + Designer.cs + Snapshot.cs

Plan B chain (6 chunks):
- A1 58898e8 Contract +2 fields (em main, done)
- A2 (this) Mig 32 schema + Config + Seed (Implementer Case 2, done)
- B Service ApproveV2Async branch (em main, in progress)
- C Mig 33 ContractLevelOpinions (Implementer, pending)
- D FE Workspace V2 (Implementer, pending)
- E FE Section 5 V2 (Implementer, pending)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/Backend/SolutionErp.Infrastructure/Persistence/Configurations/ContractConfiguration.cs

@@ -28,6 +28,15 @@ public class ContractConfiguration : IEntityTypeConfiguration<Contract>
         b.HasIndex(x => x.ProjectId);
         b.HasIndex(x => x.SlaDeadline);
         b.HasIndex(x => x.BudgetId);
+        b.HasIndex(x => x.ApprovalWorkflowId);
+
+        // FK ApprovalWorkflowId Restrict (Plan B Chunk A2 — Mig 32 mirror PE Mig 23)
+        // ApprovalWorkflowsV2 pin lúc create HĐ V2. Restrict để KHÔNG xóa workflow
+        // nếu còn HĐ pin.
+        b.HasOne<SolutionErp.Domain.ApprovalWorkflowsV2.ApprovalWorkflow>()
+            .WithMany()
+            .HasForeignKey(x => x.ApprovalWorkflowId)
+            .OnDelete(DeleteBehavior.Restrict);
 
         b.HasMany(x => x.Approvals).WithOne(a => a.Contract).HasForeignKey(a => a.ContractId).OnDelete(DeleteBehavior.Cascade);
         b.HasMany(x => x.Comments).WithOne(c => c.Contract).HasForeignKey(c => c.ContractId).OnDelete(DeleteBehavior.Cascade);

src/Backend/SolutionErp.Infrastructure/Persistence/DbInitializer.cs

@@ -68,6 +68,7 @@ public static class DbInitializer
         //   - SeedDemoContractsAsync ([DEMO] HĐ 7-type sample)
         //   - SeedDemoPurchaseEvaluationsAsync ([DEMO] PE 4 sample)
         //   - SeedSampleApprovalWorkflowsV2Async (V2 sample mẫu UAT cho type B)
+        //   - SeedSampleContractWorkflowV2Async (V2 sample mẫu UAT cho Contract — Mig 32 Plan B Chunk A2)
         // GIỮ: SeedRoles, SeedAdmin, SeedDepartments, SeedDemoUsers (30 user UAT),
         // SeedMenuTree, SeedAdminPermissions, SeedDemoMasterData (Supplier/Project
         // master), SeedContractTemplates (file template), SeedCatalogs, backfill
@@ -76,7 +77,7 @@ public static class DbInitializer
         var config = sp.GetRequiredService<IConfiguration>();
         var demoSeedDisabled = config.GetValue<bool>("DemoSeed:Disabled");
         if (demoSeedDisabled)
-            logger.LogInformation("DemoSeed:Disabled=true — skip workflow + contracts + PE + sample V2 seed (Plan T S23 t10)");
+            logger.LogInformation("DemoSeed:Disabled=true — skip workflow + contracts + PE + sample V2 seed (Plan T S23 t10 + Plan B Chunk A2 Contract V2)");
 
         await SeedRolesAsync(roleManager, logger);
         // Phase 6 rebrand: rename user email @solutionerp.local → @solutions.com.vn
@@ -106,6 +107,7 @@ public static class DbInitializer
             await SeedDemoContractsAsync(db, userManager, codeGen, logger);
             await SeedDemoPurchaseEvaluationsAsync(db, userManager, logger);
             await SeedSampleApprovalWorkflowsV2Async(db, userManager, logger);
+            await SeedSampleContractWorkflowV2Async(db, userManager, logger);
         }
 
         await WarnDefaultAdminPasswordAsync(userManager, logger);
@@ -163,6 +165,58 @@ public static class DbInitializer
         logger.LogInformation("Seeded sample ApprovalWorkflow V2 for DuyetNccPhuongAn: QT-DN-PA-V2-001 v01");
     }
 
+    // [Plan B S29 2026-05-22 Chunk A2] Seed sample workflow V2 cho ApplicableType=Contract,
+    // giúp UAT HĐ V2 nhanh không cần admin tạo qua Designer trước. Idempotent — skip
+    // nếu đã có ANY workflow Contract (admin đã tạo) HOẶC nếu thiếu user CCM seed.
+    // Mirror SeedSampleApprovalWorkflowsV2Async pattern (DuyetNccPhuongAn).
+    private static async Task SeedSampleContractWorkflowV2Async(
+        ApplicationDbContext db, UserManager<User> userManager, ILogger logger)
+    {
+        var hasAnyContract = await db.ApprovalWorkflows
+            .AnyAsync(w => w.ApplicableType == ApprovalWorkflowApplicableType.Contract);
+        if (hasAnyContract) return;
+
+        var approver = await userManager.FindByEmailAsync("binh.le@solutions.com.vn");
+        if (approver is null)
+        {
+            logger.LogWarning("SeedSampleContractWorkflowV2Async: skip — approver binh.le@solutions.com.vn (Lê Văn Bình CCM) not found");
+            return;
+        }
+
+        var ccmDept = await db.Departments.FirstOrDefaultAsync(d => d.Code == "CCM");
+
+        var wf = new ApprovalWorkflow
+        {
+            Code = "QT-HD-V2-001",
+            Version = 1,
+            ApplicableType = ApprovalWorkflowApplicableType.Contract,
+            Name = "Quy trình duyệt HĐ mẫu UAT V2",
+            Description = "Sample seed cho UAT HĐ V2 — 1 Bước Phòng CCM × 1 Cấp (Lê Văn Bình). Admin có thể clone tạo version mới qua Designer.",
+            IsActive = true,
+            IsUserSelectable = true,    // Mig 25 — user pick qua Workspace dropdown
+            ActivatedAt = DateTime.UtcNow,
+        };
+        var step = new ApprovalWorkflowStep
+        {
+            ApprovalWorkflow = wf,
+            Order = 1,
+            Name = "Bước 1 - Phòng CCM",
+            DepartmentId = ccmDept?.Id,
+        };
+        var level = new ApprovalWorkflowLevel
+        {
+            Step = step,
+            Order = 1,
+            Name = "Cấp 1",
+            ApproverUserId = approver.Id,
+        };
+        wf.Steps.Add(step);
+        step.Levels.Add(level);
+        db.ApprovalWorkflows.Add(wf);
+        await db.SaveChangesAsync();
+        logger.LogInformation("Seeded sample ApprovalWorkflow V2 for Contract: QT-HD-V2-001 v01");
+    }
+
     // Seed 4 master catalogs với defaults cho user nhập liệu Details. Idempotent:
     // skip per-table nếu đã có row (admin có thể đã thêm/sửa — không clobber).
     private static async Task SeedCatalogsAsync(ApplicationDbContext db, ILogger logger)

src/Backend/SolutionErp.Infrastructure/Persistence/Migrations/20260522051059_AddApprovalWorkflowToContract.cs

@@ -0,0 +1,60 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace SolutionErp.Infrastructure.Persistence.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddApprovalWorkflowToContract : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AddColumn<Guid>(
+                name: "ApprovalWorkflowId",
+                table: "Contracts",
+                type: "uniqueidentifier",
+                nullable: true);
+
+            migrationBuilder.AddColumn<int>(
+                name: "CurrentApprovalLevelOrder",
+                table: "Contracts",
+                type: "int",
+                nullable: true);
+
+            migrationBuilder.CreateIndex(
+                name: "IX_Contracts_ApprovalWorkflowId",
+                table: "Contracts",
+                column: "ApprovalWorkflowId");
+
+            migrationBuilder.AddForeignKey(
+                name: "FK_Contracts_ApprovalWorkflows_ApprovalWorkflowId",
+                table: "Contracts",
+                column: "ApprovalWorkflowId",
+                principalTable: "ApprovalWorkflows",
+                principalColumn: "Id",
+                onDelete: ReferentialAction.Restrict);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropForeignKey(
+                name: "FK_Contracts_ApprovalWorkflows_ApprovalWorkflowId",
+                table: "Contracts");
+
+            migrationBuilder.DropIndex(
+                name: "IX_Contracts_ApprovalWorkflowId",
+                table: "Contracts");
+
+            migrationBuilder.DropColumn(
+                name: "ApprovalWorkflowId",
+                table: "Contracts");
+
+            migrationBuilder.DropColumn(
+                name: "CurrentApprovalLevelOrder",
+                table: "Contracts");
+        }
+    }
+}

src/Backend/SolutionErp.Infrastructure/Persistence/Migrations/ApplicationDbContextModelSnapshot.cs

@@ -637,6 +637,9 @@ namespace SolutionErp.Infrastructure.Persistence.Migrations
                         .ValueGeneratedOnAdd()
                         .HasColumnType("uniqueidentifier");
 
+                    b.Property<Guid?>("ApprovalWorkflowId")
+                        .HasColumnType("uniqueidentifier");
+
                     b.Property<Guid?>("BudgetId")
                         .HasColumnType("uniqueidentifier");
 
@@ -657,6 +660,9 @@ namespace SolutionErp.Infrastructure.Persistence.Migrations
                     b.Property<Guid?>("CreatedBy")
                         .HasColumnType("uniqueidentifier");
 
+                    b.Property<int?>("CurrentApprovalLevelOrder")
+                        .HasColumnType("int");
+
                     b.Property<int?>("CurrentWorkflowStepIndex")
                         .HasColumnType("int");
 
@@ -732,6 +738,8 @@ namespace SolutionErp.Infrastructure.Persistence.Migrations
 
                     b.HasKey("Id");
 
+                    b.HasIndex("ApprovalWorkflowId");
+
                     b.HasIndex("BudgetId");
 
                     b.HasIndex("MaHopDong")
@@ -3479,6 +3487,14 @@ namespace SolutionErp.Infrastructure.Persistence.Migrations
                     b.Navigation("Budget");
                 });
 
+            modelBuilder.Entity("SolutionErp.Domain.Contracts.Contract", b =>
+                {
+                    b.HasOne("SolutionErp.Domain.ApprovalWorkflowsV2.ApprovalWorkflow", null)
+                        .WithMany()
+                        .HasForeignKey("ApprovalWorkflowId")
+                        .OnDelete(DeleteBehavior.Restrict);
+                });
+
             modelBuilder.Entity("SolutionErp.Domain.Contracts.ContractApproval", b =>
                 {
                     b.HasOne("SolutionErp.Domain.Contracts.Contract", "Contract")