Replace 'watchstar' icon in Vector with WikimediaUi default icon.
The watchstar representation is a leftover from the very beginnings of Vector, it has several shortcomings from UI-Standardization and user experience point of views:
- non-conforming to icon guidelines (different stroke line, different angles)
- unique color treatment of default, :hover and active state
- janky, unique animation, found nowhere else
- hover flicker on non-cached state
- different icon size to other standard icons around
Also take 'wikilove' icon into account.
- Check Wikilove icon on user pasges
- Check watchstar icon on article pages
- Make sure to check the temporary watchstar variant