Option to combine completion.list.selection = "auto_insert" and "preselect"

[SamuelBorn]

Feature Description

Citation from default config:

-- 'preselect' will automatically select the first item in the completion list

-- 'auto_insert' will not select any item by default, and insert the completion items automatically when selecting them

I would like to the see another option that combines them both.
The documentation could be described as:

-- 'preselect_auto_insert' will automatically select the first item in the completion list, and insert the completion items automatically when selecting them

The default preselect action though should not trigger auto_insert as this would be annoying.

So to accept the first solution one still has to press the keyboard shortcut for accept or select_and_accept.

But after selecting with select_prev and select_next, auto_insert should trigger and accepting would no longer be necessary.

[Saghen]

It should also support setting the insertion mode by keymap, as per #826, cmp.select_next({ selection = 'auto_insert' })

[SamuelBorn]

Since this plugin is beta quality and users expect breaking changes I would like to suggest to make the suggested option the new default.

[drowning-cat]

@Saghen

I think cmp.select_next should not override text selected with cmp.select_next { auto_insert = true }.

recording.mp4