refactor: save dates as unix timestamps in database

backend/internal/model/base.go

@@ -2,6 +2,7 @@ package model
 
 import (
 	"github.com/google/uuid"
+	model "github.com/stonith404/pocket-id/backend/internal/model/types"
 	"gorm.io/gorm"
 	"time"
 )
@@ -9,12 +10,13 @@ import (
 // Base contains common columns for all tables.
 type Base struct {
 	ID        string `gorm:"primaryKey;not null"`
-	CreatedAt time.Time
+	CreatedAt model.DateTime
 }
 
 func (b *Base) BeforeCreate(_ *gorm.DB) (err error) {
 	if b.ID == "" {
 		b.ID = uuid.New().String()
 	}
+	b.CreatedAt = model.DateTime(time.Now())
 	return
 }