The result is currently only used as a StringView, but a future commit
will place the result in Web::Clipboard::SystemClipboardRepresentation,
which requires a ByteString (there's no UTF-8 clipboard requirement).
This is to prepare for custom search engines. If we use AK::format, it
would be trivial for a user (or bad actor) to come up with a template
search engine URL that ultimately crashes the browser due to internal
assertions in AK::format. For example:
https://example.com/crash={1}
Rather than coming up with a complicated pre-format validator, let's
just not use AK::format. Custom URLs will signify their template query
parameters with "%s". So we can do the same with our built-in engines.
When it comes time to format the URL, we will do a simple string
replacement.
