Migrate accessories to user data

- Add user_accessory as the per-user accessory inventory table.
- Migrate old accessory wear records to user-owned accessory ids, including legacy common_accessory_m lookups for old installs.
- Allocate default accessories for newly created users and update accessory reads to use user_accessory at runtime.
- Validate accessory ownership when wearing accessories and keep existing accessory-based responses working.

Signed-off-by: Sean Du <do4suki@gmail.com>

internal/handler/api/unit/accessoryall.go

@@ -12,7 +12,7 @@ func unitAccessoryAll(ctx *gin.Context) (res any, err error) {
 	ss := session.Get(ctx)
 
 	accessoryList := []unitapischema.AccessoryList{}
-	err = ss.MainEng.Table("common_accessory_m").Find(&accessoryList)
+	err = ss.UserEng.Table("user_accessory").Where("user_id = ?", ss.UserID).Find(&accessoryList)
 	if err != nil {
 		return nil, err
 	}