Missing `hl_get_host_return_value_as_*`

[ludfjig]

Certain types don't have functions. For example, we are missing bool, double, string, vec, etc.. See flatbuffer.rs. These functions are used by our c-api.

[tiffanyiris]

Hi, is it okay if I work on this issue? Just want to make sure someone else isn't already working on this.

[ludfjig]

Hi, is it okay if I work on this issue? Just want to make sure someone else isn't already working on this.

Thanks for your interest in contributing! I'm not aware of anyone working on this, so feel free to go ahead. Let us know if you have any questions along the way—we're happy to help @tiffanyiris