refactor: replace direct Prisma calls with service layer methods for banking operations

services/account.service.ts

@@ -0,0 +1,67 @@
+import { prisma } from "@/lib/prisma"
+import type { Account } from "@/lib/types"
+
+export const accountService = {
+  async create(data: Omit<Account, "id">): Promise<Account> {
+    const created = await prisma.account.create({
+      data: {
+        name: data.name,
+        bankId: data.bankId,
+        accountNumber: data.accountNumber,
+        type: data.type,
+        folderId: data.folderId,
+        balance: data.balance,
+        currency: data.currency,
+        lastImport: data.lastImport,
+      },
+    })
+
+    return {
+      id: created.id,
+      name: created.name,
+      bankId: created.bankId,
+      accountNumber: created.accountNumber,
+      type: created.type as Account["type"],
+      folderId: created.folderId,
+      balance: created.balance,
+      currency: created.currency,
+      lastImport: created.lastImport,
+    }
+  },
+
+  async update(id: string, data: Partial<Omit<Account, "id">>): Promise<Account> {
+    const updated = await prisma.account.update({
+      where: { id },
+      data: {
+        name: data.name,
+        bankId: data.bankId,
+        accountNumber: data.accountNumber,
+        type: data.type,
+        folderId: data.folderId,
+        balance: data.balance,
+        currency: data.currency,
+        lastImport: data.lastImport,
+      },
+    })
+
+    return {
+      id: updated.id,
+      name: updated.name,
+      bankId: updated.bankId,
+      accountNumber: updated.accountNumber,
+      type: updated.type as Account["type"],
+      folderId: updated.folderId,
+      balance: updated.balance,
+      currency: updated.currency,
+      lastImport: updated.lastImport,
+    }
+  },
+
+  async delete(id: string): Promise<void> {
+    // Transactions will be deleted automatically due to onDelete: Cascade
+    await prisma.account.delete({
+      where: { id },
+    })
+  },
+}
+