Real time notification of posting status

[dtonon]

This proposal aims to make clear the status of a note that has been just sent.
When a note is posted it should immediately be displayed, with a progress bar at the bottom that explains in real time the status of the operations.

If all submits to relays went fine, the progress bar turns a neutral color, and auto hide after 5-10 seconds.

If any relays have failed, shows a summary and offers to inspect the details (pointing to the HUD modal).

If relays fail at a ratio greater than 50%, or if there is even a single block for unauthorized access (missing payment), the progress bar remains highlighted to make the problem clear.