feat: add vendor optional fields and configuration hooks

- Implemented VendorOptionalFields component to handle optional vendor details (mobile, email, address) with validation.
- Created useCustomerConfig hook to load optional customer field settings from Sales configuration.
- Developed useProcurementConfig hook to manage Procurement configuration flags.
- Introduced accessConfigApi for managing access configuration settings.
- Added openingBalancesApi for handling opening balances operations.
- Created procurementConfigApi for managing procurement configuration settings.
- Implemented nav-routes for permission-based routing.
- Developed PDF generation for purchase orders with dynamic vendor and item details.
- Added purchase-order tax helpers for tax calculations and formatting.
- Defined types for opening balances and related operations.

Testing/e2e/specs/global.setup.ts

@@ -2,6 +2,9 @@ import { test as setup } from "@playwright/test"
 import { LoginPage } from "../pages/LoginPage"
 import { env, AUTH_STORAGE_STATE } from "../support/env"
 
+// NOTE: E2E_ADMIN_EMAIL must be an administrator in the ERP itself (users.RoleId -> the role flagged IsAdmin; Settings -> Users).
+// Being "admin" in AuthHex no longer grants anything: the ERP reads the role from its own database on every request.
+//
 // Runs once before the "chromium" project (see playwright.config.ts `dependencies`). Logs
 // in through the real UI form - the session is an httpOnly cookie (docs/11 §2.0), so there
 // is no token to inject; driving the form is the only way to obtain it - then saves cookies