[Guard] Guard setup form UX enchancements

[dofi4ka]

Describe the feature

When you paste URL to the spreadsheet it does not fit in input and looks kinda ugly.
Leaving document links untitled also not a good practice.

Suggested solution

Immediately after pasting URL to the spreadsheet we can:

1. Show that URL is correct
2. Show whether service-gmail has access to it or not
3. Get document name from Google API and suggest it for title

Additional context

No response

[dantetemplar]

So?