Allow rebinding ToggleSearchMode and ToggleReplaceMode

It looks like these are hardcoded here https://github.com/yassinebridi/serpl/blob/2a195169e14d3a871f31cac89bfef68c3524c048/src/components/search.rs#L109 https://github.com/yassinebridi/serpl/blob/2a195169e14d3a871f31cac89bfef68c3524c048/src/components/replace.rs#L81 Would like to rebind to deconflict with my terminal multiplexer setup.