Add enums, AuthService, and integrate backend registration endpoints

- Add separate enum files: BuildingType, PropertyStatus, BookingStatus, CommissionType, IdentityType, UserRole, City, LoginMethod, OwnerType, CustomerType
- Add AuthService (addToken/getToken/deleteToken)
- Update api.js: use AuthService, add Owner/Add and Customer/Add endpoints
- Update login page to use AuthService for token storage
- Rewrite owner register: 3-step flow with OwnerType dropdown, backend integration, OTP verification
- Rewrite tenant register: 2-step flow with CustomerType dropdown, backend integration, OTP verification
- Update homepage and property detail to use enums instead of hardcoded maps
- Update AddPropertyForm to import from enums directly
- Add console logs and status toasts linked to API response messages

app/enums/LoginMethod.js

@@ -0,0 +1,11 @@
+/**
+ * LoginMethod Enum
+ * Authentication method type
+ * Used in: Login page, OTP verification
+ */
+const LoginMethod = Object.freeze({
+  EMAIL: 'email',
+  PHONE: 'phone',
+});
+
+export { LoginMethod };