LSP "Problems" in VSC/Windows - bad file uri

[dgriffie79]

The "Problems" panel does isn't working on windows, in that clicking on the problem does not take you to the file location because the file URI is messed up as in the screenshot. This causes an annoying window to open up saying the path isn't valid, rather than jumping to the compile error in the code.

It looks like there are two issues:

1. the compiler json output is wrong on windows because it doesn't escape the \ in the file path. You can see this by running onyx check --error-format json and the file paths will not have the \\ as they should for json encoded strings.

2. the uri with the drive letter is encoded weird, so that it looks like 'file://c:/...' which would be an invalid file URI because C: is not a hostname. This commented out call to uri_encode does fix this issue on windows