Adds HTML title elements to templates that extend either `base.html`,
`portico.html` or `portico_signup.html`, and that are not website
portico landing pages that will use the `PAGE_TITLE` variable to set
the HTML title element (see following commit in series).
Also, updates some templates for missing translation tags.
As a general rule, we want the title element (and page content)
translated. Exceptions that are updated in this commit are templates
used in the development environment, analytics templates that are used
by staff and templates related to Zephyr.
This reimplements our Zoom video call integration to use an OAuth
application. In addition to providing a cleaner setup experience,
especially on zulipchat.com where the server administrators can have
done the app registration already, it also fixes the limitation of the
previous integration that it could only have one call active at a time
when set up with typical Zoom API keys.
Fixes#11672.
Co-authored-by: Marco Burstein <marco@marco.how>
Co-authored-by: Tim Abbott <tabbott@zulipchat.com>
Signed-off-by: Anders Kaseorg <andersk@mit.edu>