feat(e2e): add Playwright end-to-end tests for authentication, GRN, production, stock transfers, and adjustments

- Introduced Playwright configuration for e2e testing.
- Implemented authentication tests to validate login functionality.
- Created tests for GRN (Goods Receipt Note) to ensure proper stock handling.
- Developed production run tests to verify lifecycle and stock posting.
- Added stock transfer tests to check movement between warehouses.
- Implemented stock adjustment tests for positive and negative adjustments.
- Established API seeder for test data setup and verification.
- Enhanced utility functions for UI interactions and response handling.

Backend/ERPCore/appsettings.Development.json

@@ -6,7 +6,7 @@
     }
   },
   "ConnectionStrings": {
-    "DefaultConnection": "Host=localhost;Port=5432;Database=ERPCoreDev;Username=postgres;Password=root"
+    "DefaultConnection": "Host=localhost;Port=5432;Database=ERPCoreTest;Username=postgres;Password=root"
   },
   "AuthHex": {
     "BaseUrl": "http://localhost:5011"

Backend/ERPCore/package-lock.json

@@ -0,0 +1,6 @@
+{
+  "name": "ERPCore",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {}
+}