feat: Implement command flag management for rclone configurations

- Added functionality to manage command flags and their values in the configuration form.
- Updated the database schema to include a new field for storing command flag values.
- Enhanced backend logic to process and store flag values for non-boolean flags during configuration creation and updates.
- Improved the user interface to dynamically require destination fields based on selected commands.
- Refactored related templates and handlers to support the new command flag management features.

internal/db/db.go

@@ -126,6 +126,7 @@ type TransferConfig struct {
 	// Rclone command fields
 	CommandID              uint   `gorm:"default:1" form:"command_id"` // Default to 'copy' command ID (1)
 	CommandFlags           string `form:"command_flags"`               // JSON string of selected flags
+	CommandFlagValues      string `form:"command_flag_values"`         // JSON string of flag values by ID
 	DeleteAfterTransfer    *bool  `gorm:"default:false" form:"delete_after_transfer"`
 	SkipProcessedFiles     *bool  `gorm:"default:true" form:"skip_processed_files"`
 	MaxConcurrentTransfers int    `gorm:"default:4" form:"max_concurrent_transfers"` // Number of concurrent file transfers

internal/db/migrations/010_add_rclone_command_to_config.go

@@ -78,6 +78,10 @@ func AddRcloneCommandToConfig() *gormigrate.Migration {
 				return err
 			}
 
+			if err := tx.Exec(`ALTER TABLE transfer_configs ADD COLUMN command_flag_values TEXT DEFAULT NULL`).Error; err != nil {
+				return err
+			}
+
 			return nil
 		},
 		Rollback: func(tx *gorm.DB) error {
@@ -90,6 +94,10 @@ func AddRcloneCommandToConfig() *gormigrate.Migration {
 				return err
 			}
 
+			if err := tx.Exec(`ALTER TABLE transfer_configs DROP COLUMN command_flag_values`).Error; err != nil {
+				return err
+			}
+
 			return nil
 		},
 	}