Add descriptions and tooltips for domain request statuses

[gabydisarli]

Issue description

We've long had descriptions and tooltips for domain statuses, but we don't have the same for domain request statuses. In recent usability testing and research, we learned that users are confused by our domain request statuses and could use more clarification.

In the spirit of iterative improvement, we should try to limit the scope of this ticket to just add descriptions and tooltips that describe out current domain request statuses: Started, Submitted, In review, Action needed, Rejected. In the user insights below, many wondered about specific status questions related to FEB agencies, or wanted sub-steps. While this is worthy to explore, we should try to limit the scope as much as possible to prevent the work becoming too large. Or optionally, this could turn into a parent ticket to sub-issues that explore these other insights.

Insights from users related to domain request statuses

• Wasn't sure what "submitted" meant. Does it mean he submitted it or it has been submitted to OMB? 
• Wasn't sure if "in review" mean review by CISA or by OMB.
• Wants to see why request is in "action needed" status. What action is needed? 
• Long period of time between submitted and approved. Stakeholders were checking on status. Could you add sub-steps?

Acceptance criteria

• Create descriptions for current domain request statuses. Create a content doc similar to the Domain Status Definitions document to track content. Keep in mind that these will have to support multiple user roles/permissions in org model who can view domain requests but can't take action on them.
• (optional) Mock up in Figma some examples of the tooltips and definitions on the domain request table and domain request overview page. In the end, these shouldn't have to be fully documented in Figma, our source of truth should be the Google Doc.
• Share for approval
• Create dev ticket for implementation

Additional context

No response

Links to other issues

No response