[Feature] [Breakdown] Add option to export by scenes

[hyuri]

It's helpful to have sheets for each scene, containing location, time of day, INT/EXT, scene name, and all elements in that scene. Especially when we are preparing breakdown sheets.

Right now, we have all scenes in a single sheet, "Breakdown", that contains all scenes in the horizontal position with the name of elements in the vertical position, which makes it hard to navigate.

Especially needed until we get the Scheduling module and have the ability to export breakdown sheets (#184).