This is a first use of the new hooks system, which allows customizing
cosmic-comp at compile-time.
In this case, the view() function of CosmicWindow / CosmicStack is
hooked and the hook can change what is rendered as the header bar.
Signed-off-by: Yureka <yuka@yuka.dev>
Allows other programs to depend on the cosmic_comp library crate and
start a cosmic-comp in their process by calling `cosmic_comp::run()`.
Later, customization parameters can be added to `run()`.
Note that the interface of the cosmic_comp library crate is not stable
in any way and might change anytime.
Signed-off-by: Yureka <yuka@yuka.dev>
