When the chatter is in side mode (lg+ sizes), its size can become quite small
(since it is proportional with the width of the viewport). Add a static minimal
width so that the display stays readable.
Change the border color of the buttons in the knowledge header so that when the
chatter is displayed, it has a better contrast (the chatter button is a toggle
on-off).
Task-2858428
X-original-commit: 7d07f6f52886d1d7b86fd008fab579ffd8e71702
Part-of: odoo/odoo#93088
abd-msyukyu-odoo
8a2380bf36