persistence / savestate to prevent user map loss

[BellBlitzKing]

Another contributor was experimenting with a Save-State that prevents map loss if the user refreshes the session.
mekaron#3

I'm not sure how to transplant their code but would be super useful is added to the main blurymind version to prevent map creation loss.

[blurymind]

I could try to cherry pick the fix and test it :)
Didn't know people were forking my tiny tile map editor already and doing so much

Wow, @mekaron this is awesome work !
You integrated a window manager with resizable areas and lots of other things

But its no longer a single file module that can be easily dropped in other projects and the out of the box experience starts with empty map with red tiles.

Maybe the single file approach makes it kind of a pain to work with. We could introduce typescript and a bundler instead - that way we can get it to export a single file module, but the source code can be split in different files.

The layout is done with golden-layout library that is directly imported from a url. Its adding dependencies, which this project is trying to be zero dependencies.

If I change it to be:

• does have dependencies (npm managed)
• uses typescript and vite for bundling
• had bundling process to pack it with all dependencies in a single module

that would improve dev experience here for sure.

I think priority would be to first convert it to typescript. I would welcome a pr for that :D alot of bugs in it come from not having type safety