[FR] Kanban board UX improvements

### Description

- scrolling automatically vertically in a group according to focus traversal if the group has more cards than can fit on the screen
- scrolling automatically horizontally if there are more groups than can fit on the screen according to focus traversal
- scrolling automatically to the bottom of the group once a card has been created from the bottom (now it's scrolling to the bottom BEFORE the card has been created)
- allow left and right arrow keys. right now it's implemented like notion: up and down to go previous/next card in a group, and once the user reaches the end, the next up/down will move to the next/previous group. To implement this feature would require getting the widget position and size of the cards in each group and figure out which card in the adjacent group is nearest. Simply using index to navigate to the card in the adjacent group isn't a good solution because some cards may be tall and others be very short.
- implement a rectangular select tool to select multiple cards with one mouse drag

### Impact

Users of the kanban board

### Additional Context

_No response_