Hi Gavin,
AI integration probably requires different key hooks based on what the capabilities are. I'm not sure it's something we could add a base framework for since it's a very open-ended concept. That being said, SyntaxEditor does expose all the event sinks you need to track key and typing input. And intra-text adornments are ideal for rendering AI suggestions.
In fact, for v25.1 we will be adding an option that allows intra-text adornments to appear at the end of the tagged range instead of at the start. This was done specifically to support things like AI suggestions that may be placed after the last character on a line.