[Tile] Add rules of interactive elements in actionable tiles

[thyhmdo]

Original issue: carbon-design-system/carbon#13030

Prompt

From a discussion with Mike Gower, we should consider rules to have a certain number of interactive elements or links within the actionable expandable tiles. Consider both with and without interactive elements expandable tiles.

---

Accepted criteria

From Gower - If you want users to be able to navigate tiles efficiently, do not put a whole bunch of click targets in tiles. Remember that actionable children within tiles add additional tab stops for keyboard users, which leads to much longer time on task. In an ideal world we’d recommend no more than one (two?) actions on a tile.

Consideration
When there is a complicated pattern of multiple interactive elements / components inside an actionable tile

• It takes time for users to move through the entire card content
• There are lots of tab stops for keyboard users
• It can cause confusion of multiple click targets within a card
• Provide meaningful ways to understand hidden interactive elements within the expandable tiles

---

Tasks

Explore and Playback

• Explore more examples from early iteration Figma file
• Review feedback from the PAL community [Tile] Expandable tiles: Adding guidance and rules for interactive elements #3499
• Playback to Michael Gower and the designer team

Doc update

• Flesh out / add above to guidance under Expandable tiles
• Draw distinction between fully clickable expandable tile and expandable with chevron button
• Add a visual example
• Add an extra Do / Don't

Interesting Tile finding
https://dataplatform.cloud.ibm.com/projects/799f83b8-f29a-4702-b147-af52f6203299?context=wx