iPad mini - fix trailing bar button item collapsing behavior

[tonisevener]

Phabricator: https://phabricator.wikimedia.org/T416188

Notes

Fixing some design review feedback for ellipses buttons.

• Unified ellipses buttons (Saved, Article toolbar, Activity) to use ellipses icon without the circle.
• Lots of modifications to ensure it collapses as expected on iPad mini, instead of showing two ellipses buttons. See https://wikimedia.slack.com/archives/C4DDMJ9CH/p1775070010289729

https://docs.google.com/spreadsheets/d/1gqnz3OMliE2feOLPS9oUAR5i3qWSwDoDGpYWC4YPXNU/edit?gid=492238000#gid=492238000 (Rows 12-14)

Note I could not visually separate the ellipses from the tabs and profile icon without regression on the iPad mini collapsing behavior. So we are keeping it separated for now.

Test Steps

1. Run on iPad mini, ensure if there isn't enough room, it only shows a single ellipses button instead of multiple.
2. Run on larger iPad, ensure icons display the same as iPhone.
3. Ensure ellipses icons do not have circle around them.

Before:

After: