Mdx-deck: Allow to set Presenter component via theme

[codepunkt]

I'm currently working on my own presenter that emphasizes my Notes compared the current and next slides. I've found an easy way to change the Presenter component via theme - which basically requires to merge the themes in MDXDeck component instead of the Provider and then, based on the theme, either render the theme-provided Presenter or the default one. The merged could then also be passed to the Provider in order to not merge it twice.

It's not a lot of code changes and i'd love to contribute them to not have to maintain my fork. What do you think?

[codepunkt]

This would also easily allow things like #46.

Here is a short clip of the presenter that i've built for my presentations - just to give you an idea:

[jxnblk]

Thanks! This is a great idea! I was thinking of supporting this with Gatsby theme's shadowing feature in the next release, but I'll try to take a look at the PR in the next few days

[pomber]

I also have my own Presenter, this would be very useful.

[codepunkt]

@jxnblk any news on this?

[jxnblk]

Sorry, definitely wanna get this in, I just haven't had as much time to focus on mdx-deck recently. Hoping to go through this over the weekend, so hang tight 🙏