add model identities and restore httpx router

backend/internal/models/inbox_item.go

@@ -3,15 +3,18 @@ package models
 import "time"
 
 type SenlinAgentInboxItem struct {
-	ID         uint   `gorm:"primaryKey"`
-	ProjectID  uint   `gorm:"index;not null"`
-	CreatedBy  uint   `gorm:"index;not null"`
-	SourceType string `gorm:"not null"`
-	Title      string
-	Body       string
-	Status     string `gorm:"not null;default:open"`
-	CreatedAt  time.Time
-	UpdatedAt  time.Time
+	ID                uint   `gorm:"primaryKey"`
+	Identity          string `gorm:"type:char(36);uniqueIndex"`
+	ProjectID         uint   `gorm:"index;not null"`
+	ProjectIdentity   string `gorm:"type:char(36);index"`
+	CreatedBy         uint   `gorm:"index;not null"`
+	CreatedByIdentity string `gorm:"type:char(36);index"`
+	SourceType        string `gorm:"not null"`
+	Title             string
+	Body              string
+	Status            string `gorm:"not null;default:open"`
+	CreatedAt         time.Time
+	UpdatedAt         time.Time
 }
 
 func (SenlinAgentInboxItem) TableName() string {