In zulip/zulip#28468, we plan to rename "stream" to "channel" in the Zulip UI.

Ideally, the mobile apps will use the same terminology as the web app on the server version that the user is on.

Related issues:

• Recognize "channel" as operator in narrow links #5860
• Generate narrow links using "channel" operator, not "stream", if server is recent #5861