Expands web app instructions for setting a status to have
a tab for via user card and via personal menu.
Adds instructions for clearing a status via user card, via
personal menu, and for mobile.
Adds new svg file for the icon used in zulip/mobile for
clearing a status.
Fixes#29415.
Co-authored-by: Lauryn Menard <lauryn@zulip.com>
JohnLu2004