`copilot` should make it easy to understand and fix configuration errors

### Describe the bug

When `copilot` has issues reading from configuration file, it displays a error in the timeline that can be unhelpful for fixing the configuration problem:

```
× Failed to add folder to trusted list: Failed to add trusted folder: Failed to read configuration from /Users/andyfeller/.copilot/config.json: [
{
"code": "invalid_type",
"expected": "string",
"received": "undefined",
"path": [
"last_logged_in_user",
"host"
],
"message": "Required"
},
{
"code": "invalid_type",
"expected": "string",
"received": "undefined",
"path": [
"last_logged_in_user",
"login"
],
"message": "Required"
}
]
```

### Affected version

_No response_

### Steps to reproduce the behavior

State of the configuration file at the time:

```json
{
"banner": "always",
"theme": "auto",
"logged_in_users": [],
"last_logged_in_user": {},
"trusted_folders": []
}
```

### Expected behavior

Whether this was caused by a user modifying the configuration file or some unexpected circumstance, users should be presented with actions / commands / steps to fix their problems.

In this case here, I don't know if the only fix is to blow away the configuration file and start over OR if there was some way to ask Copilot to get this back into a good state.

Either way, the information presented to the user could use improvement:

- Use an expandable box for the technical details
- Have the timeline entry summary explain there is a problem with their configuration file
- Present users with a prompt with actions for fixing it

### Additional context

_No response_