Seed and self-heal Gift Certificate Liability account 2500 (audit O5)

Account 2500 is resolved by number as the GC liability (GiftCertificatesController),
but the per-tenant seeder never created it — so tenants onboarded after the
AccountingGapsPhase2 migration had no GC liability account and gift-certificate GL
postings silently no-op'd. The default-company seeder also created 2500 as
"Long-Term Loan", mislabeling that company's GC obligations.

  - SeedDataService.Accounts: seed 2500 "Gift Certificate Liability" (IsSystem)
  - SeedData: seed 2500 as GC liability; move long-term loan to 2900
  - EnsureSystemAccountsAsync: self-heal — rename a 2500 still named "Long-Term Loan"
    (preserving user renames) and ensure a 2500 exists
  - migration FixGiftCertificateLiabilityAccount: move long-term loan to 2900 where a
    2500="Long-Term Loan" exists without a 2900, relabel the mislabeled 2500, and
    safety-net insert a 2500 for any company lacking one

Non-destructive: no account Id/number/balance is changed (same pattern as O1).
Verified on dev: existing GC-liability rows preserved, no spurious accounts added.
All audit findings O1-O5 resolved. Build clean; 291 unit tests pass; migration applied.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/ACCOUNTING_AUDIT.md

@@ -98,6 +98,24 @@ migration applied to the dev database successfully.
 
 Verification of O3+O4: `dotnet build` clean; `dotnet test tests/PowderCoating.UnitTests` → **291 passed**.
 
+### O5 — Gift Certificate Liability 2500 missing for new tenants / mislabeled on default company — **RESOLVED**
+- **Root cause (same shape as O1):** 2500 is resolved by number as the GC liability
+  (`GiftCertificatesController`). The `AccountingGapsPhase2` migration seeded it for tenants existing at
+  deploy, but (a) the per-tenant seeder `SeedDataService.Accounts.cs` never created a 2500, so tenants
+  onboarded afterward had **no GC liability account** and GC GL postings silently no-op'd; and (b) the
+  default-company seeder `SeedData.cs` created 2500 as **"Long-Term Loan"**, so that company's GC
+  obligations were mislabeled (and the migration's `NOT EXISTS` guard skipped it).
+- **Fix:**
+  - `SeedDataService.Accounts.cs` now seeds **2500 "Gift Certificate Liability" (IsSystem)**.
+  - `SeedData.cs` now seeds 2500 as GC liability and moves the long-term loan to **2900**.
+  - `EnsureSystemAccountsAsync` self-heals: renames any 2500 still named "Long-Term Loan" → "Gift
+    Certificate Liability" (preserving user renames) and ensures a 2500 exists.
+  - Migration `20260620002950_FixGiftCertificateLiabilityAccount`: moves long-term loan to 2900 where a
+    2500="Long-Term Loan" exists and no 2900 is present; relabels the mislabeled 2500; safety-net inserts a
+    2500 for any company lacking one. Non-destructive (no Id/number/balance changes); Down is best-effort.
+- Verified on the dev DB: existing 2500 GC-liability rows preserved; no spurious accounts added; build
+  clean; migration applied; **291 unit tests pass**.
+
 ---
 
 ## Remaining (non-O1–O4) — known lower-risk follow-up

src/PowderCoating.Infrastructure/Data/SeedData.cs

@@ -1362,7 +1362,9 @@ New accounts walk through an 18-step setup wizard to configure company informati
             // 2300 = Customer Deposits liability (resolved by number in the deposit GL posting code); payroll is at 2400.
             new() { AccountNumber = "2300", Name = "Customer Deposits",        AccountType = AccountType.Liability,  AccountSubType = AccountSubType.OtherCurrentLiability, IsSystem = true,  IsActive = true, CompanyId = company.Id, CreatedAt = now },
             new() { AccountNumber = "2400", Name = "Payroll Liabilities",      AccountType = AccountType.Liability,  AccountSubType = AccountSubType.OtherCurrentLiability, IsSystem = false, IsActive = true, CompanyId = company.Id, CreatedAt = now },
-            new() { AccountNumber = "2500", Name = "Long-Term Loan",          AccountType = AccountType.Liability,  AccountSubType = AccountSubType.LongTermLiability,  IsSystem = false, IsActive = true, CompanyId = company.Id, CreatedAt = now },
+            // 2500 = Gift Certificate Liability (resolved by number in the GC GL posting code); long-term loan moved to 2900.
+            new() { AccountNumber = "2500", Name = "Gift Certificate Liability", AccountType = AccountType.Liability, AccountSubType = AccountSubType.OtherCurrentLiability, IsSystem = true,  IsActive = true, CompanyId = company.Id, CreatedAt = now },
+            new() { AccountNumber = "2900", Name = "Long-Term Loan",          AccountType = AccountType.Liability,  AccountSubType = AccountSubType.LongTermLiability,  IsSystem = false, IsActive = true, CompanyId = company.Id, CreatedAt = now },
 
             // ── Equity ──────────────────────────────────────────────────────
             new() { AccountNumber = "3000", Name = "Owner's Equity",          AccountType = AccountType.Equity,     AccountSubType = AccountSubType.OwnersEquity,       IsSystem = true,  IsActive = true, CompanyId = company.Id, CreatedAt = now },

src/PowderCoating.Infrastructure/Migrations/20260620002950_FixGiftCertificateLiabilityAccount.cs

@@ -0,0 +1,123 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace PowderCoating.Infrastructure.Migrations
+{
+    /// <inheritdoc />
+    public partial class FixGiftCertificateLiabilityAccount : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            // O5 remediation. Account 2500 is resolved by number as the Gift Certificate Liability
+            // (GiftCertificatesController), but the default-company chart seeded it as "Long-Term Loan",
+            // so GC obligations were mislabeled there and the AccountingGapsPhase2 GC-liability seed was
+            // skipped by its NOT EXISTS guard.
+
+            // 1) Preserve the long-term loan account: move it to 2900 for any company whose 2500 is still
+            //    named "Long-Term Loan" and that lacks a 2900. (Companies onboarded via the per-tenant
+            //    seeder already have a 2900 "Business Loan", so the NOT EXISTS guard leaves them alone.)
+            migrationBuilder.Sql(@"
+                INSERT INTO Accounts
+                    (AccountNumber, Name, AccountType, AccountSubType,
+                     IsSystem, IsActive, Description,
+                     CompanyId, CreatedAt, IsDeleted, CurrentBalance, OpeningBalance)
+                SELECT '2900', 'Long-Term Loan',
+                    2,   -- AccountType.Liability
+                    11,  -- AccountSubType.LongTermLiability
+                    0, 1, 'Long-term equipment or business loan',
+                    c.Id, GETUTCDATE(), 0, 0, 0
+                FROM Companies c
+                WHERE c.IsDeleted = 0
+                  AND EXISTS (SELECT 1 FROM Accounts a WHERE a.CompanyId = c.Id
+                              AND a.AccountNumber = '2500' AND a.IsDeleted = 0 AND a.Name = 'Long-Term Loan')
+                  AND NOT EXISTS (SELECT 1 FROM Accounts a WHERE a.CompanyId = c.Id
+                                  AND a.AccountNumber = '2900' AND a.IsDeleted = 0);
+            ");
+
+            // 2) Relabel the mislabeled 2500 to Gift Certificate Liability (only where it still carries the
+            //    old default name, so a user's own rename is preserved). Id / number / balance untouched.
+            migrationBuilder.Sql(@"
+                UPDATE Accounts
+                SET Name = 'Gift Certificate Liability',
+                    Description = 'Outstanding gift certificate obligations owed to certificate holders',
+                    IsSystem = 1
+                WHERE AccountNumber = '2500' AND IsDeleted = 0 AND Name = 'Long-Term Loan';
+            ");
+
+            // 3) Safety net: ensure every company has a 2500 Gift Certificate Liability (covers any tenant
+            //    onboarded after AccountingGapsPhase2 ran that never received one — without it GC GL no-ops).
+            migrationBuilder.Sql(@"
+                INSERT INTO Accounts
+                    (AccountNumber, Name, AccountType, AccountSubType,
+                     IsSystem, IsActive, Description,
+                     CompanyId, CreatedAt, IsDeleted, CurrentBalance, OpeningBalance)
+                SELECT '2500', 'Gift Certificate Liability',
+                    2,   -- AccountType.Liability
+                    12,  -- AccountSubType.OtherCurrentLiability
+                    1, 1, 'Outstanding gift certificate obligations owed to certificate holders',
+                    c.Id, GETUTCDATE(), 0, 0, 0
+                FROM Companies c
+                WHERE c.IsDeleted = 0
+                  AND NOT EXISTS (SELECT 1 FROM Accounts a WHERE a.CompanyId = c.Id
+                                  AND a.AccountNumber = '2500' AND a.IsDeleted = 0);
+            ");
+
+            migrationBuilder.UpdateData(
+                table: "PricingTiers",
+                keyColumn: "Id",
+                keyValue: 1,
+                column: "CreatedAt",
+                value: new DateTime(2026, 6, 20, 0, 29, 46, 909, DateTimeKind.Utc).AddTicks(3976));
+
+            migrationBuilder.UpdateData(
+                table: "PricingTiers",
+                keyColumn: "Id",
+                keyValue: 2,
+                column: "CreatedAt",
+                value: new DateTime(2026, 6, 20, 0, 29, 46, 909, DateTimeKind.Utc).AddTicks(3981));
+
+            migrationBuilder.UpdateData(
+                table: "PricingTiers",
+                keyColumn: "Id",
+                keyValue: 3,
+                column: "CreatedAt",
+                value: new DateTime(2026, 6, 20, 0, 29, 46, 909, DateTimeKind.Utc).AddTicks(3982));
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            // Best-effort reversal: the 2500 relabel is intentionally NOT undone (reverting would
+            // re-introduce the mislabel), and 2500 rows are left in place since most pre-date this
+            // migration. Only soft-delete the empty 2900 accounts this migration added.
+            migrationBuilder.Sql(@"
+                UPDATE Accounts SET IsDeleted = 1
+                WHERE AccountNumber = '2900' AND IsDeleted = 0 AND Name = 'Long-Term Loan' AND CurrentBalance = 0;
+            ");
+
+            migrationBuilder.UpdateData(
+                table: "PricingTiers",
+                keyColumn: "Id",
+                keyValue: 1,
+                column: "CreatedAt",
+                value: new DateTime(2026, 6, 19, 23, 31, 4, 905, DateTimeKind.Utc).AddTicks(7611));
+
+            migrationBuilder.UpdateData(
+                table: "PricingTiers",
+                keyColumn: "Id",
+                keyValue: 2,
+                column: "CreatedAt",
+                value: new DateTime(2026, 6, 19, 23, 31, 4, 905, DateTimeKind.Utc).AddTicks(7618));
+
+            migrationBuilder.UpdateData(
+                table: "PricingTiers",
+                keyColumn: "Id",
+                keyValue: 3,
+                column: "CreatedAt",
+                value: new DateTime(2026, 6, 19, 23, 31, 4, 905, DateTimeKind.Utc).AddTicks(7619));
+        }
+    }
+}

src/PowderCoating.Infrastructure/Migrations/ApplicationDbContextModelSnapshot.cs

@@ -7241,7 +7241,7 @@ namespace PowderCoating.Infrastructure.Migrations
                         {
                             Id = 1,
                             CompanyId = 0,
-                            CreatedAt = new DateTime(2026, 6, 19, 23, 31, 4, 905, DateTimeKind.Utc).AddTicks(7611),
+                            CreatedAt = new DateTime(2026, 6, 20, 0, 29, 46, 909, DateTimeKind.Utc).AddTicks(3976),
                             Description = "Standard pricing for regular customers",
                             DiscountPercent = 0m,
                             IsActive = true,
@@ -7252,7 +7252,7 @@ namespace PowderCoating.Infrastructure.Migrations
                         {
                             Id = 2,
                             CompanyId = 0,
-                            CreatedAt = new DateTime(2026, 6, 19, 23, 31, 4, 905, DateTimeKind.Utc).AddTicks(7618),
+                            CreatedAt = new DateTime(2026, 6, 20, 0, 29, 46, 909, DateTimeKind.Utc).AddTicks(3981),
                             Description = "5% discount for preferred customers",
                             DiscountPercent = 5m,
                             IsActive = true,
@@ -7263,7 +7263,7 @@ namespace PowderCoating.Infrastructure.Migrations
                         {
                             Id = 3,
                             CompanyId = 0,
-                            CreatedAt = new DateTime(2026, 6, 19, 23, 31, 4, 905, DateTimeKind.Utc).AddTicks(7619),
+                            CreatedAt = new DateTime(2026, 6, 20, 0, 29, 46, 909, DateTimeKind.Utc).AddTicks(3982),
                             Description = "10% discount for premium customers",
                             DiscountPercent = 10m,
                             IsActive = true,

src/PowderCoating.Infrastructure/Services/SeedDataService.Accounts.cs

@@ -66,6 +66,9 @@ public partial class SeedDataService
             new Account { AccountNumber = "2300", Name = "Customer Deposits",          AccountType = AccountType.Liability,  AccountSubType = AccountSubType.OtherCurrentLiability, IsSystem = true,  IsActive = true, Description = "Deposits received from customers before an invoice is created; cleared when applied to an invoice", CompanyId = company.Id, CreatedAt = now },
             new Account { AccountNumber = "2350", Name = "Customer Credits",           AccountType = AccountType.Liability,  AccountSubType = AccountSubType.OtherCurrentLiability, IsSystem = true,  IsActive = true, Description = "Store credit owed to customers (credit memos not yet applied)", CompanyId = company.Id, CreatedAt = now },
             new Account { AccountNumber = "2400", Name = "Payroll Liabilities",        AccountType = AccountType.Liability,  AccountSubType = AccountSubType.OtherCurrentLiability, IsSystem = false, IsActive = true, Description = "Payroll taxes and withholdings owed",       CompanyId = company.Id, CreatedAt = now },
+            // 2500 Gift Certificate Liability — credited when a GC is issued, debited when redeemed/voided
+            // (resolved by number in GiftCertificatesController). IsSystem because the GL posting depends on it.
+            new Account { AccountNumber = "2500", Name = "Gift Certificate Liability",  AccountType = AccountType.Liability,  AccountSubType = AccountSubType.OtherCurrentLiability, IsSystem = true,  IsActive = true, Description = "Outstanding gift certificate obligations owed to certificate holders", CompanyId = company.Id, CreatedAt = now },
             new Account { AccountNumber = "2900", Name = "Business Loan",             AccountType = AccountType.Liability,  AccountSubType = AccountSubType.LongTermLiability,   IsSystem = false, IsActive = true, Description = "Long-term equipment or business loan",       CompanyId = company.Id, CreatedAt = now },
 
             // ── EQUITY ────────────────────────────────────────────────────────
@@ -235,6 +238,46 @@ public partial class SeedDataService
             added++;
         }
 
+        // 2500 has always been resolved by number as the Gift Certificate Liability (GiftCertificatesController),
+        // but the default-company seed created it as "Long-Term Loan" — so GC obligations were mislabeled there.
+        // Rename it (only where it still carries the old default name) and mark it system.
+        var legacyGcAcct = await _context.Set<Account>()
+            .IgnoreQueryFilters()
+            .FirstOrDefaultAsync(a => a.CompanyId == company.Id && a.AccountNumber == "2500"
+                                   && !a.IsDeleted && a.Name == "Long-Term Loan");
+        if (legacyGcAcct != null)
+        {
+            legacyGcAcct.Name        = "Gift Certificate Liability";
+            legacyGcAcct.Description = "Outstanding gift certificate obligations owed to certificate holders";
+            legacyGcAcct.IsSystem    = true;
+            legacyGcAcct.UpdatedAt   = now;
+            await _context.SaveChangesAsync();
+        }
+
+        // 2500 Gift Certificate Liability — ensure it exists for companies that never got one (e.g. tenants
+        // onboarded after the AccountingGapsPhase2 migration ran). Without it, GC GL postings silently no-op.
+        var has2500 = await _context.Set<Account>()
+            .IgnoreQueryFilters()
+            .AnyAsync(a => a.CompanyId == company.Id && a.AccountNumber == "2500" && !a.IsDeleted);
+
+        if (!has2500)
+        {
+            _context.Set<Account>().Add(new Account
+            {
+                AccountNumber  = "2500",
+                Name           = "Gift Certificate Liability",
+                AccountType    = AccountType.Liability,
+                AccountSubType = AccountSubType.OtherCurrentLiability,
+                IsSystem       = true,
+                IsActive       = true,
+                Description    = "Outstanding gift certificate obligations owed to certificate holders",
+                CompanyId      = company.Id,
+                CreatedAt      = now
+            });
+            await _context.SaveChangesAsync();
+            added++;
+        }
+
         return added;
     }
 }