Add state message to the UI Flow Run page

[zhen0]

First check

• [X] I added a descriptive title to this issue.
• [X] I used the GitHub search to find a similar request and didn't find it.
• [X] I searched the Prefect documentation for this feature.

Prefect Version

2.x

Describe the current behavior

Currently, the UI does not show state message information. This info can be useful if a flow run is not picked up and can give context about why.

Describe the proposed behavior

Add a field in the flow run details tab to show the last state message

Example Use

I have an agent with incorrect permissions to access where my flow code is stored. The flow run fails and never gets to running so there are no logs. The UI does not give useful information but if I look in the network tab and check out flow_run.state.message I get useful info.

Additional context

No response

[zhen0]

Add this info to the flow run details tab / well.

[zhen0]

Better example