feat: Update entity types to include specific ID types and adjust DTO mappings

backend/internal/domain/entities/customer.go

@@ -3,7 +3,7 @@ package entities
 import "github.com/oklog/ulid/v2"
 
 type Customer struct {
-	ID        ulid.ULID
+	EntityBase
 	Name      string
 	CompanyID int
 }

backend/internal/domain/entities/project.go

@@ -3,7 +3,7 @@ package entities
 import "github.com/oklog/ulid/v2"
 
 type Project struct {
-	ID         ulid.ULID
+	EntityBase
 	Name       string
 	CustomerID int
 }