Draw attention to NPC Monologue speech bubbles

Character speech bubble is always in the same place, so you know where to look and easily notice when the character talks (or so I assume).

However, when "an NPC" speaks, you can quite easily miss the speech bubble - it can appear anywhere on screen and your eye is not really drawn to it.

LZ has zombies growling behind the doors that have the blood puddle under them, this can be tested with those.

Scope:
* try out different animations or some other ways to draw attention to the npc monologue speech bubble
* implement one (or even several that can be configured in interactions.json)

Start by reproducing the NPC monologue with the zombies growling behind doors marked by blood puddles in LZ. Try attention-drawing animations or other approaches, then implement one or more configurable options in interactions.json; done means NPC speech bubbles are harder to miss during play.

Written by the indexing model from the issue text.