feat: add jump action

[idan-at]

Allows moving the cursor to the URL location when selected through the picker

Fixes #72

[axieax]

Thanks for your contribution @idan-at! Since the picker shows unique links, I think the jump action should populate the jumplist with all instances of the url for easy navigation.

In that case I think we can simplify the code to use string.find to scan the entire buffer for the url_without_prefix, and work backwards to use the start of the word in case the match is to the middle of a URL, i.e. (buffer with https://www.google.com and www.google.com should set the jumplist to the beginning of both URLs).

[axieax]

Thanks for making the changes @idan-at! Actually, I just had a closer think about the expected behaviour for the jump action, and I think populating the jumplist doesn't make any sense (not the intended purpose for navigating between urls). Sorry but let's revert the changes to the commit before, and clarify in the docs that the expected behaviour is to navigate to the first instance in the buffer.

[idan-at]

Hey, took me a while but finally got to it :)