Make `DelegateSizeHelper` take a `QQuickItem` rather than a width value and move `TimelineDelegate` to use it rather than duplicting the code.
This requires the creation of `LibNeoChat` so that both the main and timeline modules can get access to the class.
Note: ideally more stuff will go into `LibNeoChat` but it turns out our dependencies are kinda spaghetti like and so will take some untangling.
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.
The focus here is to make threads use the standard message content system rather than having a special implementation.
To achieve this the threadroot content model will now get a thread body component which will visualise the thread model with all the other messages. The latest message in the thread will then just ask for the thread root content model and show that.
Note: in order to stop a cyclical dependency with MessageComponentChooser and new base version has been added which is just missing ThreadBodyComponent and and the main version is now inherited from that with ThreadBodyComponent added.
There are 2 main reason for doing this:
1. Because I can, I wanted to see if I could do it
2. It gets rid of the janky qml re parenting stuff so should be faster.
Steal the look of itinerary items from itinerary but simplified. Also includes new support for flights and restaurants
This adds previews for downloaded pdfs and code files.
