This changes client methods so that they return the IPC response's
return value directly - instead of the response struct - for IPC
methods which only have a single return value.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
Since WM operations are moved to a separate endpoint pair, Taskbar now
uses those to perform window management related operations.
Additionally, it now explicitly declares to WindowServer that it is a
window manager.
Now that WindowServer broadcasts the system theme using an anonymous
file, we need clients to pledge "recvfd" so they can receive it.
Some programs keep the "shared_buffer" pledge since it's still used for
a handful of things.
Window icons in Taskbar were previously received in WM events with
shbuf ID's. Now that Gfx::ShareableBitmap is backed by anonymous files,
we can easily switch to using those.
