Greasy Fork

If the toolbar already exists, add the button immediately

Run on document-idle, not document-start.

This should help the button appear more reliably by waiting a bit longer for the page to load all elements.

- update styling to work in dark mode (steal styling from 'Review changes' button)

- match their new URL: app.graphite.com
- update matching regex to handle dash (-) in repo or project name (thanks @gaosong2101!)

Fixes issue where the button might show twice