Fix install and discard bad behaviour

[NBKelly]

I did a few things here.

• First, you cannot drag cards during select prompts. This should prevent unwitting players from discarding from hq in the wrong way, or trashing programs in the wrong during install.
• Second, if you opt to trash some programs (but not enough), we can retry the install and ask again (I wish there was a trivial way to determine if enough MU was selected, but there are probably issues with it and effects)
• Third, you cannot attempt to trash the host of a card you are installing during installation (according to the rules team). I added a function in hosting to check if a card happens to be an ancestor of another card to facilitate this. This is nice, because doing that before actually locked up the game without presenting any errors, so we get a double-whammy here.

Closes #7824
Closes #6893 (by preventing the player from discarding like that)

[NoahTheDuke]

Good chance.