Add message and user commands for conveniently selecting a message/user range

[Rekkonnect]

A way more user-friendly way to perform actions is to let the user select the individual messages and apply a command on them. Since we're dealing with ranges, the selection of the range will precede the selection of the action. Ideally, the user has to click on "Begin Range" and "End Range" on the selected messages, after which selections they will be prompted with a list of available actions for the given ranges (filtered based on the message types).

Too lazy to curate the above text, same applies for users.