The function considers @**all**, @**everyone**, @**stream**,
and @**topic** as wildcard mentions.
Earlier, the function didn't have a check to match @**topic**
in the message_content.
Following the issue #23380 and PR #25038, this commit changes all
occurences of `uri` into `url` in all comments, local variables,
handlebars templates (.hbs) function names and their callers in
all `.js` and `.ts` files.
This lets us simplify the long-ish ‘../../static/js’ paths, and will
remove the need for the ‘zrequire’ wrapper.
Signed-off-by: Anders Kaseorg <anders@zulip.com>