Move the reaction delegate into the bubble so it can be instantiated by the Content model. This aims to make sure we only instantiate it when needed rather than for every event. You can now hover the event to show the ReactionComponent with a button to add a reaction if none are currently present
Added bonus ReactionModel no longer needs an event pointer, the event ID is enough to get reaction from the room so things are less likely to blow up.
Move the storage of MessageContentModels to the room in the same manner as memeber objects to prevent duplication but mainly to make the system easier to maintain going forward with things like threads for example. This requires the creation of a MessageContentFilterModel as the same model may be used in multiple places, sometimes with the author showning sometimes not.
