Bind Feishu identity to OpenVPN sessions and refine management UI

backend/internal/model/model.go

@@ -28,6 +28,17 @@ type IdentityGrant struct {
 	Consumed  bool      `gorm:"default:false"`
 }
 
+// IdentityProfile is display metadata from a verified Feishu user-info response.
+// It grants no VPN permissions and contains no upstream access token.
+type IdentityProfile struct {
+	ID        uint      `gorm:"primaryKey"`
+	Issuer    string    `gorm:"uniqueIndex:idx_identity_profile;size:256"`
+	AppID     string    `gorm:"uniqueIndex:idx_identity_profile;size:128"`
+	Subject   string    `gorm:"uniqueIndex:idx_identity_profile;size:256"`
+	Name      string    `gorm:"size:256"`
+	UpdatedAt time.Time
+}
+
 // TrafficSample 流量时间序列采样（每 60 秒一次，用于趋势图） // Logan.Li
 type TrafficSample struct {
 	ID        uint      `gorm:"primaryKey" json:"id"`
@@ -175,6 +186,7 @@ type AuditLog struct {
 
 // VPNSession 在线会话（跨协议统一记录拨号用户的连接状态） // Logan.Li
 type VPNSession struct {
+	DisplayName    string     `gorm:"size:256" json:"display_name,omitempty"`
 	ID             uint       `gorm:"primaryKey" json:"id"`
 	TunnelID       uint       `gorm:"index" json:"tunnel_id"`
 	VPNUserID      uint       `gorm:"index" json:"vpn_user_id"`
@@ -191,6 +203,7 @@ type VPNSession struct {
 
 // ConnectionLog 连接审计日志（连接/断开/认证失败/配额超额/异常流量） // Logan.Li
 type ConnectionLog struct {
+	DisplayName string    `gorm:"size:256" json:"display_name,omitempty"`
 	ID        uint      `gorm:"primaryKey" json:"id"`
 	TunnelID  uint      `gorm:"index" json:"tunnel_id"`
 	Username  string    `gorm:"size:128" json:"username"`