patch 9.1.1638: completion: not possible to delay the autcompletion

patch 9.1.1638: completion: not possible to delay the autcompletion

Problem:  completion: not possible to delay the autcompletion
Solution: add the 'autocompletedelay' option value (Girish Palya).

This patch introduces a new global option 'autocompletedelay'/'acl' that
specifies the delay, in milliseconds, before the autocomplete menu
appears after typing.

When set to a non-zero value, Vim waits for the specified time before
showing the completion popup, allowing users to reduce distraction from
rapid suggestion pop-ups or to fine-tune the responsiveness of
completion.

The default value is 0, which preserves the current immediate-popup
behavior.

closes: #17960

Signed-off-by: Girish Palya <girishji@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>