There is no rich text editor right now. There are quicktags.
There are several versions of a quicktags plugin for bbPress: not sure which one is best or still works.
For images, if people can host it somewhere, you want the Allow Images plugin.
If you want to allow people to upload attachments (including images) you want the bbPress Attachments plugin.
If you read the instructions for the bbPress Attachments plugin, you will see how they can attach an image first, then embed that image in their post.