Fix Hardcore mode (where the world switches to Survival after death).

I propose making Hardcore mode a one-time experience. In other words, if a player dies in the world—even if they enable cheats and switch back to Survival mode—it remains Survival mode, not Hardcore.

Essentially, after a player dies in a Hardcore world, a button would appear allowing them to either switch the world to Survival mode to keep playing or keep it as a memento.

Those who truly want the Hardcore experience could simply delete the world themselves instead of switching it to Survival, since they wouldn't need to keep the world as a keepsake.

So, I’m not suggesting removing, simplifying, or otherwise altering Hardcore mode itself. I simply want to eliminate the feeling of losing the world upon death—or the alternative of respawning via cheats.