Optimized Bad Dreams' code

[LOuroboros]

Description

Earlier today as I was looking into #2430, I realized by checking the code that composes Bad Dreams' effect, that the way in which we handle it is a bit more complex than it needs to be. It's similar to how I feel about the code for Intimidate's effect in the vanillla game.

Because of that, I took it upon myself to streamline the code that handles the effect of the ability a little bit.
Instead of having 2 or 3 different loops directly involved in the ability's effect, now there's only one and it's completely handled in the battle script of the ability's effect directly. This allowed me to free up Cmd_trygetbaddreamstarget which was never really needed.

As I tested the ability's behavior in the modern games, I noticed that the behavior of the Ability Pop Up wasn't accurate; the pop up needs to stay on screen until the ability is done performing its effect, so I updated that.
I also noticed that the text string used by Bad Dreams was different in ORAS so I updated that too.

badDreamsORAS.mp4

I'm submitting this as a Draft for now, since the changes to sText_BadDreamsDmg may need to be reverted depending on the result of this poll.

Discord contact info

Lunos#4026

[LOuroboros]

The results of the poll speak for themselves, no one disabled the ability pop up, as such, the PR is ready for review since I won't need to revert the change to sText_BadDreamsDmg 👀