User updates their profile (PATCH 'api/v1/users/:id')

As a logged-in User,
When I visit users/:id,
Then I see a button to update User information

```
PATCH 'api/v1/users/:id'

request: {
info_being_patched:
}

response: {
user_id:
message: patch successful
}
```

Start by locating the API entry point for PATCH /api/v1/users/:id and read the existing user update and authentication handling around it. Define the accepted patch payload and verify the endpoint updates the logged-in user's information while returning the requested user_id and success message.

Written by the indexing model from the issue text.