feat(borders): add border manager module

This commit removes all border-related code from process_command,
process_event etc. and centralizes it in the new border_manager module.

Instead of trying to figure out where in process_event and
process_command we should make border-related changes, a notification
gets sent to a channel that border_manager listens to whenever an event
or command has finished processing.

The border_manager listener, upon receiving a notification, acquires a
lock on the WindowManager instance and updates borders for the focused
workspace on every monitor; this allows us to centralize all edge case
handling within the border_manager listener's loop.

Borders on workspaces that lose focus are now destroyed and recreated
when those workspaces regain focus, instead of trying to share
individual border instances across workspaces.

A number of common edge cases that have been addressed in this commit
are:

* Paused window manager
* Floating workspaces
* Maximized windows
* Fullscreen videos
* Monocle containers
* Ghost borders on workspace switching
* Incorrect focused window border colours

Global state related to borders has also been moved into the
border_manager module, which also tracks the state of border objects
(BORDER_STATE), their rects (RECT_STATE) and their focus kinds
(FOCUS_STATE).

This allows us to now track multiple borders per-container, enabling
unfocused border windows for the first time.

Additionally, the Z-Order for border windows is now also configurable.

ActiveWindowBorderColours has been expanded to include Unfocused, but in
order to not introduce a breaking configuration change for end users,
all members of this struct have been made Option<Colour>.

komorebi/src/lib.rs

@@ -1,4 +1,4 @@
-pub mod border;
+pub mod border_manager;
 pub mod com;
 #[macro_use]
 pub mod ring;
@@ -53,7 +53,6 @@ use color_eyre::Result;
 use komorebi_core::config_generation::IdWithIdentifier;
 use komorebi_core::config_generation::MatchingRule;
 use komorebi_core::config_generation::MatchingStrategy;
-use komorebi_core::ActiveWindowBorderStyle;
 use komorebi_core::ApplicationIdentifier;
 use komorebi_core::HidingBehaviour;
 use komorebi_core::Rect;
@@ -197,13 +196,6 @@ lazy_static! {
         )
     };
 
-    static ref ACTIVE_WINDOW_BORDER_STYLE: Arc<Mutex<ActiveWindowBorderStyle>> =
-        Arc::new(Mutex::new(ActiveWindowBorderStyle::System));
-
-    static ref BORDER_RECT: Arc<Mutex<Rect>> =
-        Arc::new(Mutex::new(Rect::default()));
-
-
     // Use app-specific titlebar removal options where possible
     // eg. Windows Terminal, IntelliJ IDEA, Firefox
     static ref NO_TITLEBAR: Arc<Mutex<Vec<String>>> = Arc::new(Mutex::new(vec![]));
@@ -220,18 +212,7 @@ pub static DEFAULT_CONTAINER_PADDING: AtomicI32 = AtomicI32::new(10);
 pub static INITIAL_CONFIGURATION_LOADED: AtomicBool = AtomicBool::new(false);
 pub static CUSTOM_FFM: AtomicBool = AtomicBool::new(false);
 pub static SESSION_ID: AtomicU32 = AtomicU32::new(0);
-pub static BORDER_ENABLED: AtomicBool = AtomicBool::new(false);
-pub static BORDER_HWND: AtomicIsize = AtomicIsize::new(0);
-pub static BORDER_HIDDEN: AtomicBool = AtomicBool::new(false);
-pub static BORDER_COLOUR_SINGLE: AtomicU32 = AtomicU32::new(0);
-pub static BORDER_COLOUR_STACK: AtomicU32 = AtomicU32::new(0);
-pub static BORDER_COLOUR_MONOCLE: AtomicU32 = AtomicU32::new(0);
-pub static BORDER_COLOUR_CURRENT: AtomicU32 = AtomicU32::new(0);
-pub static BORDER_WIDTH: AtomicI32 = AtomicI32::new(8);
-pub static BORDER_OFFSET: AtomicI32 = AtomicI32::new(-1);
 
-// 0 0 0 aka pure black, I doubt anyone will want this as a border colour
-pub const TRANSPARENCY_COLOUR: u32 = 0;
 pub static REMOVE_TITLEBARS: AtomicBool = AtomicBool::new(false);
 
 pub static HIDDEN_HWND: AtomicIsize = AtomicIsize::new(0);