完善站点运营设置：分路由管理、登录可见评论、邮件模板内联与关闭注册 SSR。

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/model/operations.go

@@ -0,0 +1,66 @@
+package model
+
+import "time"
+
+// ModuleConfig is versioned independently; secrets are encrypted by the service.
+type ModuleConfig struct {
+	Name      string    `gorm:"primaryKey;size:32" json:"name"`
+	Version   int64     `json:"version"`
+	Data      string    `gorm:"type:text" json:"-"`
+	UpdatedAt time.Time `json:"updated_at"`
+}
+
+type SettingsAudit struct {
+	ID        uint      `gorm:"primaryKey" json:"id"`
+	ActorID   uint      `json:"actor_id"`
+	Module    string    `gorm:"size:32" json:"module"`
+	Action    string    `gorm:"size:64" json:"action"`
+	Fields    string    `gorm:"type:text" json:"fields"`
+	Result    string    `gorm:"type:text" json:"result"`
+	CreatedAt time.Time `gorm:"index" json:"created_at"`
+}
+
+type ActionCounter struct {
+	Key       string `gorm:"primaryKey;size:64"`
+	Count     int
+	ExpiresAt time.Time `gorm:"index"`
+}
+
+// MailTask retains no plaintext credentials, codes or links.
+type MailTask struct {
+	ID        uint      `gorm:"primaryKey" json:"id"`
+	Dedupe    string    `gorm:"uniqueIndex;size:64" json:"-"`
+	Kind      string    `gorm:"size:32" json:"kind"`
+	Recipient string    `gorm:"size:256" json:"recipient"`
+	Payload   string    `gorm:"type:text" json:"-"`
+	Status    string    `gorm:"index;size:32" json:"status"`
+	Attempts  int       `json:"attempts"`
+	Summary   string    `gorm:"size:128" json:"summary"`
+	NextAt    time.Time `gorm:"index" json:"-"`
+	CreatedAt time.Time `json:"created_at"`
+	UpdatedAt time.Time `json:"updated_at"`
+}
+
+type EmailChallenge struct {
+	Hash      string    `gorm:"primaryKey;size:64"`
+	Email     string    `gorm:"index;size:256"`
+	Purpose   string    `gorm:"size:32"`
+	ExpiresAt time.Time `gorm:"index"`
+	Used      bool
+}
+
+// Every remote object pins the immutable configuration revision that wrote it.
+type StoredObject struct {
+	ID         string    `gorm:"primaryKey;size:64" json:"id"`
+	ConfigName string    `gorm:"size:64;index" json:"-"`
+	Key        string    `gorm:"size:512" json:"-"`
+	MIME       string    `gorm:"size:128" json:"-"`
+	Public     bool      `json:"-"`
+	CreatedAt  time.Time `json:"created_at"`
+}
+
+type TemporaryUpload struct {
+	ID           string    `gorm:"primaryKey;size:64"`
+	RelativePath string    `gorm:"size:512"`
+	CreatedAt    time.Time `gorm:"index"`
+}