An improved way of preserving and replaying original mappings

[homedirectory]

Certain mappings, such as scrolling in floating windows, try to be non-intrusive, and when they can't be applied they use nvim_feedkeys() to replay the original mapping. However, this simple approach does not always work. For example, I have <C-n> remapped to gt which stops working and instead scrolls by a single line even when there are no floating windows.

This change brings a more sophisticated mechanism of capturing and replaying the original mapping. The implementation was inspired by anuvyklack/keymap-amend.nvim