GoExtract sends incorrect location to LSP about vim-go

[bhcleek]

I can duplicate what you're describing. Interestingly, Vim's help has this to say about the visual markers:

							*'<* *`<*
'<  `<			To the first line or character of the last selected
			Visual area in the current buffer.  For block mode it
			may also be the last character in the first line (to
			be able to define the block).

							*'>* *`>*
'>  `>			To the last line or character of the last selected
			Visual area in the current buffer.  For block mode it
			may also be the first character of the last line (to
			be able to define the block).  Note that 'selection'
			applies, the position may be just after the Visual
			area.

Which corresponds to what we're seeing here. I'll see if there's a correct way to figure out the full extent of the visual selection.