Servers with the (enabled) capability extended-join will include the
account name of whoever joins in the event string. If it's there, catch
the user into the user array so we don't have to WHOIS them later.
May not be broken out into a separate top-level function as it must be
able to evaluate __traits(compiles, { alias _ = .hasChannelAwareness; })
at compile time.
Adds a user to the IRCPlugin's IRCPluginState.users array, potentially including their services account name.
Servers with the (enabled) capability extended-join will include the account name of whoever joins in the event string. If it's there, catch the user into the user array so we don't have to WHOIS them later.
May not be broken out into a separate top-level function as it must be able to evaluate __traits(compiles, { alias _ = .hasChannelAwareness; }) at compile time.