Common on many, many guns. Looks to be a very straight forward repair if only the lug and short rib are loose. With a bit of heat during the bend the short rib will likely be fine. I can put a small bead on the rear of the rib and refit but would hope to avoid that if possible. The key to getting a good solder joint is getting everything clean so the solder wants to bond rather than fight you. I bead blast the under side of ribs before tinning with rosin flux. Cant get it too hot or the flux burns so I use just an iron on the ribs and both a torch and and iron on the barrels. Not a hard job but requires a bit of diligence. Proper placement of the lug can be tricky but it is very important as that is what usually keeps the fore end tight to the action.
