Add display mode chooser and align screen-sharing styles

Open the four display modes from XF86Display or the external-monitor bar icon. Reuse output reconciliation and confirmation for manual layout changes, and notify the shell when monitor state changes.

Release backdrop locks before render-element queries to prevent blurred popups from freezing the compositor. Cover popup open, update and close with regression tests.

Share translucent card styles between display modes and capture sources, show focus rings during keyboard navigation, and align picker buttons, label sizing and footer spacing with system modals.

feresectl/src/main.rs

@@ -111,6 +111,13 @@ fn parse_args(args: impl IntoIterator<Item = String>) -> Result<(String, Value),
     let command = args.next().ok_or_else(usage)?;
     let positional = args.collect::<Vec<_>>();
     let payload = match command.as_str() {
+        "output-layout" => {
+            exactly_one(&command, &positional, "internal-only, external-only, extend or mirror")?;
+            if !["internal-only", "external-only", "extend", "mirror"].contains(&positional[0].as_str()) {
+                return Err("unknown display layout".into());
+            }
+            json!({ "layout": positional[0] })
+        }
         "output-profile" => {
             exactly_one(&command, &positional, "profile name or auto")?;
             json!({ "name": positional[0] })
@@ -170,6 +177,7 @@ fn parse_args(args: impl IntoIterator<Item = String>) -> Result<(String, Value),
         | "get-workspaces"
         | "get-outputs"
         | "outputs"
+        | "toggle-display-mode"
         | "output-profiles"
         | "output-confirm"
         | "output-revert"
@@ -208,13 +216,26 @@ fn socket_path() -> Result<PathBuf, io::Error> {
 }
 
 fn usage() -> String {
-    "usage: feresectl outputs\n       feresectl output-profiles\n       feresectl <output-confirm|output-revert>\n       feresectl output-profile <name|auto>\n       feresectl output-internal <on|off>\n       feresectl autostart\n       feresectl screenshot [--geometry \"x,y WxH\"]\n       feresectl screenshot-window <window-id>\n       feresectl <focus|move|resize> <direction>\n       feresectl <workspace|move-to-workspace> <index>\n       feresectl workspace-back-and-forth\n       feresectl <focus-last-window|focus-mru-next|focus-mru-previous>\n       feresectl <toggle-floating|toggle-maximized|toggle-fullscreen|toggle-layout|toggle-overview|toggle-keybinding-guide>\n       feresectl <cycle-column-width|center-column|consume|expel|close|exit|request-logout>\n       feresectl <get-focused-window|get-windows|get-workspaces|get-outputs|reload-config>".to_owned()
+    "usage: feresectl outputs\n       feresectl output-profiles\n       feresectl <output-confirm|output-revert>\n       feresectl output-layout <internal-only|external-only|extend|mirror>\n       feresectl toggle-display-mode\n       feresectl output-profile <name|auto>\n       feresectl output-internal <on|off>\n       feresectl autostart\n       feresectl screenshot [--geometry \"x,y WxH\"]\n       feresectl screenshot-window <window-id>\n       feresectl <focus|move|resize> <direction>\n       feresectl <workspace|move-to-workspace> <index>\n       feresectl workspace-back-and-forth\n       feresectl <focus-last-window|focus-mru-next|focus-mru-previous>\n       feresectl <toggle-floating|toggle-maximized|toggle-fullscreen|toggle-layout|toggle-overview|toggle-keybinding-guide>\n       feresectl <cycle-column-width|center-column|consume|expel|close|exit|request-logout>\n       feresectl <get-focused-window|get-windows|get-workspaces|get-outputs|reload-config>".to_owned()
 }
 
 #[cfg(test)]
 mod tests {
     use super::*;
 
+    #[test]
+    fn display_mode_commands_validate_layouts() {
+        for layout in ["internal-only", "external-only", "extend", "mirror"] {
+            assert_eq!(
+                parse_args(["output-layout".into(), layout.into()]).unwrap().1,
+                json!({"layout":layout})
+            );
+        }
+        assert!(parse_args(["output-layout".into(), "docked".into()]).is_err());
+        assert!(parse_args(["output-layout".into()]).is_err());
+        assert!(parse_args(["toggle-display-mode".into()]).is_ok());
+    }
+
     #[test]
     fn shortcut_hint_command_rejects_extra_arguments() {
         assert_eq!(