Added basic support for input_regions

[manthanabc]

Attempts to solve #110

This creates an interface to dynamically set input region, which can be edited by user by means of a new action

   // Simple application
   LayershellCustomActoin::SetInputRegion(|region| {
            region.add(0, 0, 5000, 5000);
            region.subtract(0, 0, 50, 50);
    }))
   // Multi-Window application
   Message::SetInputRegion { 
      set_region: |region| { 
        region.add(500,500,1920,1080); 
      }, id: WindowId
   }

I'm marking this as draft, any suggestions would be much appreciate since its my first time contributing here.
This also adds nessasory changes to to_layer_message macro, and to multi window mode.

[Decodetalkers]

Here can use expect, because wl_compositor should exist

[Decodetalkers]

This will exist after doing bind, so here can also use expect

[Decodetalkers]

Can you add an example for this new apo?

[manthanabc]

should i just create an examples folder and add this example there instead?, since i feel like readme should have a minimal example only

[Decodetalkers]

I mean add an examples folder and add this example instead. And it will be better to add comments in the place of this code

[Decodetalkers]

I think it is already fine to be merged

[Decodetalkers]

Now finally , you need to fix the clippy problem

[manthanabc]

I think it is already fine to be merged

Yea, but we can't yet pass closures to set_input, unless it does not capture the environment variables (so are automatically converted to fn). which seems really useful, since without it the shapes have to be pretty much statically decided at compile time. to allow for it i would either need to

• change SetInputRegion(&'a (dyn Fn(&WlRegion)) which would mean i'd need to introduce the <'a> everywhere LayershellCustomAction is contained which i dont really like
• or just wrap it in box<dyn Fn(&WlRegion)> which would need user to also wrap the closure in box which is fine but it does heap allocation so might not be desirable

i cannot decide which one i should do
edit: typos

[manthanabc]

@Decodetalkers does this look good 👀 ??

[Decodetalkers]

ok, I will merge it