[Feature] Throw error if the popup cannot be drawn above or below the current line. #12
Description
Describe the issue
Currently, if the popup has not enough space to be drawn above or below the current line, its creation is undefined behaviour.
Proposal
Throw an error if there is not enough space for the popup to be drawn, letting the user know why renaming failed. In order to make it possible to still rename, default to the basic vim.lsp.buf.rename() functionality, instead of the popup.