fix(ui): 自定义工具表单 overflow-y-scroll→auto + 认证方式NONE翻译改为'无' + Captain文档爬虫/同步后端

backend/internal/model/captain_models.go

@@ -182,7 +182,7 @@ type CaptainDocument struct {
 	AccountID           uint               `gorm:"index;not null" json:"account_id"`
 	AssistantID         uint               `gorm:"index;not null" json:"assistant_id"`
 	Name                string             `gorm:"size:255" json:"name"`
-	ExternalLink        string             `gorm:"size:2048;not null" json:"external_link"`
+	ExternalLink        string             `gorm:"size:2048" json:"external_link"`
 	Content             string             `gorm:"type:text" json:"content,omitempty"`
 	ContentFingerprint  string             `gorm:"size:64" json:"content_fingerprint,omitempty"`
 	Status              DocumentStatus     `gorm:"size:50;default:in_progress;not null" json:"status"`
@@ -192,6 +192,11 @@ type CaptainDocument struct {
 	LastSyncErrorCode   string             `gorm:"size:50" json:"last_sync_error_code,omitempty"`
 	Metadata            json.RawMessage    `gorm:"type:jsonb;serializer:json" json:"metadata,omitempty"`
 
+	// File upload metadata (PDF support)
+	FileSize    int64  `gorm:"default:0" json:"file_size,omitempty"`
+	ContentType string `gorm:"size:100" json:"content_type,omitempty"`
+	FileURL     string `gorm:"size:2048" json:"file_url,omitempty"`
+
 	// Relationships
 	Assistant CaptainAssistant           `gorm:"foreignKey:AssistantID" json:"assistant,omitempty"`
 	Responses []CaptainAssistantResponse `gorm:"foreignKey:DocumentableID" json:"responses,omitempty"`