feat(transactions): işlem servisi, bakiye hesaplama, satıcı kuralları ve izolasyon

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/features/accounts/service.ts

@@ -1,6 +1,7 @@
 import "server-only";
 import { Types } from "mongoose";
 import { getHouseholdDetail, resolveMembership } from "@/features/households/service";
+import { computeAccountDeltas } from "@/features/transactions/service";
 import { tr } from "@/i18n/tr";
 import { fail, ok, type ActionResult } from "@/lib/action-result";
 import { diffFields, writeAudit } from "@/lib/audit";
@@ -94,12 +95,12 @@ type Lean = {
 const canSeeBalance = (a: Lean, viewerId: string) =>
   !a.isPrivate || String(a.ownerUserId) === viewerId;
 
-/** FAZ 6b: açılış bakiyesi + işlemler. Şimdilik açılış bakiyesi. */
-function computeBalance(a: Lean): number {
-  return a.openingBalanceMinor;
+/** Güncel bakiye = açılış bakiyesi + gerçekleşmiş işlemlerin etkisi (tek doğruluk kaynağı: işlemler). */
+function computeBalance(a: Lean, deltas: ReadonlyMap<string, number>): number {
+  return a.openingBalanceMinor + (deltas.get(String(a._id)) ?? 0);
 }
 
-function toView(a: Lean, viewerId: string): AccountView {
+function toView(a: Lean, viewerId: string, deltas: ReadonlyMap<string, number>): AccountView {
   const visible = canSeeBalance(a, viewerId);
   return {
     id: String(a._id),
@@ -113,7 +114,7 @@ function toView(a: Lean, viewerId: string): AccountView {
     archived: Boolean(a.archivedAt),
     isPrivate: a.isPrivate,
     ownerUserId: a.ownerUserId ? String(a.ownerUserId) : null,
-    balanceMinor: visible ? computeBalance(a) : null,
+    balanceMinor: visible ? computeBalance(a, deltas) : null,
     openingBalanceMinor: visible ? a.openingBalanceMinor : null,
     openingDate: toIstanbulYmd(a.openingDate),
     overdraft: a.overdraft?.enabled ? a.overdraft : null,
@@ -140,7 +141,10 @@ export async function listAccounts(
   const rows = (await AccountModel.find(filter).lean<Lean[]>()).sort(
     (a, b) => a.order - b.order || compareTr(a.name, b.name),
   );
-  const household = await HouseholdModel.findById(m.householdId).select({ settings: 1 }).lean();
+  const [household, deltas] = await Promise.all([
+    HouseholdModel.findById(m.householdId).select({ settings: 1 }).lean(),
+    computeAccountDeltas(m.householdId),
+  ]);
   const includePrivate = household?.settings?.includePrivateAccountsInTotals ?? true;
 
   const totals: AccountTotals = {
@@ -158,12 +162,12 @@ export async function listAccounts(
       continue;
     }
     if (!visible) totals.includesHidden = true;
-    const balance = computeBalance(a);
+    const balance = computeBalance(a, deltas);
     if (isLiabilityType(a.type)) totals.cardDebtMinor += balance;
     else totals.assetsMinor += balance;
   }
   totals.netMinor = totals.assetsMinor + totals.cardDebtMinor;
-  return { accounts: rows.map((a) => toView(a, userId)), totals };
+  return { accounts: rows.map((a) => toView(a, userId, deltas)), totals };
 }
 
 /** Form → belge alanları. Kart için açılış borcu negatif saklanır. */