Hello,
I had the same situation, by mistake I deleted my sword, I though I was deleting a blue item and unfortunately was my sword. Like others in this forum I have 3 characters and I want to have the three swords and obviously with the current system is not possible.
We just want to get the quest again. This is the first time I dismantle a weapon by mistake. Lest hope we can hear from #Bungie soon.
Mistake or on purpose, the fact remains that they (bungie) are not giving enough information concerning those swords. And we cannot "repair" that mistake by ourselves. So we're lost in the darkness till forever.