[FR] Board move multiple items to a group with shortcut

[Xazin]

Description

We can now select cards in a board with Shift + click or holding Shift and using down/up arrow keys.

We have a shortcut for moving ONE card to previous/next group, I'd like to enable this behavior for when multiple cards are selected, this is the intended behavior:

Cards selected from multiple groups

• When moving cards to previous or next using the shortcut, all cards should move to the group of the card that is selected furthest to the left/right.
• This means that if we have groups A, B, and C, and a card is selected in both group A, and B, and the shortcut , is used to move items to the left, all selected cards will end up in group A.
• This means that if we have groups A, B, and C, and a card is selected in both group A, and B, and the shortcut . is used to move items to the right, all selected cards will end up in group B.

Cards selected from same group

• When moving cards to previous/next group, all cards should move from the same group to the previous/next group

Impact

Empower kanban users

Additional Context

See appflowy_flutter\lib\plugins\database\board\presentation\widgets\board_shortcut_container.dart

[KaranKaira]

@Xazin , can u pls assign this to me
working on this