Changes

add base entities and initial repositories

Entities added:
- BaseEntity: generic superclass with id attribute.
- PersonEntity: extends BaseEntity with personal data.
- AdminEntity: extends PersonEntity.
- UserEntity: extends PersonEntity and includes loyaltyPoints.

Repositories created:
- AdminRepository
- PersonRepository
- UserRepository

All entities are annotated with @Entity (except BaseEntity as @MappedSuperclass),
and repositories extend JpaRepository to enable database access with Spring Data JPA.
 (commit: d6c45f3)

Implemented Branch and Reservation entities with relationships and their respective repositories.
 (commit: 836a1c1)

Add Notification, Product, and Service entitities and repositories

- Created Notification, Product, and Service entity classes with JPA annotations
- Added corresponding repository interfaces for each entity
 (commit: f060a57)

Add associations in UserEntity

- Added @OneToMany relationships to Reserva and CarritoDeCompra.
- Annotated associations with @PodamExclude to avoid issues during tests.
 (commit: a447d58)

Add associations in UserEntity

- Added @OneToMany relationships to ReservationEntity and ShoppingCartEntity.
- Annotated associations with @PodamExclude to avoid issues during tests.
 (commit: fa3b940)

Add e-commerce entities and data layer

Implement multimedia, payment and shopping cart entities, as well as
their corresponding repository interfaces to support the core business
operations of the DogSpa application.

The new entities provide comprehensive data modeling for:
- MultimediaEntity: handles images and media content for branches,
  services and products with proper JPA relationships
- PaymentEntity: manages payment transactions with amount, method,
  date and status tracking linked to shopping carts
- ShoppingCartEntity: orchestrates the shopping experience connecting
  users, products and payments through well-defined associations

Additionally cleans up unnecessary blank lines in MultimediaEntity
annotations for better code readability and consistency.
 (commit: a7517ba)

Add initial associations in UserEntity

- Added @OneToMany relationship with ReservationEntity.
- Added @OneToOne relationship with ShoppingCartEntity.
- Annotated associations with @PodamExclude to avoid issues during tests.
 (commit: b906b0a)

fix(repositories): correct JpaRepository generic types for MultimediaRepository, PaymentRepository and ShoppingCartRepository
 (commit: 44a4c2a)

Renamed admitrados to adminEntity
 (commit: e8b1606)

fix(AdminEntity, AdminRepository): add @ManyToOne relation with UserEntity and update repository reference from AdministradorEntity to AdminEntity
 (commit: d5926fd)