Breaks opening folds with "n"/"N" (with foldopen+=search)

I've noticed that folds are not opened during search with `n` when vim-oblique is being used.

I think it would be a good fix to call `zv` automatically in case `'foldopen'` contains `search`.

I am not sure if there is a way to undo `zv` when going to the next/prev search result (which I assume Vim does for its internal `n`/`N`).

It works with `foldopen=all` btw (!), and this appears to be different from enabling all options separately (i.e. adding `jump` and `insert` to the default setting).

No files or tests are named. Start by reproducing a search with n/N while using vim-oblique and foldopen+=search, then inspect the plugin's search handling and Vim's fold behavior. Done means folds open during searches without breaking navigation to the next or previous result.

Written by the indexing model from the issue text.