quickshell: run a single shared gamemode monitor

GamemodePill is instantiated per screen Variant, so it spawned one
long-lived gdbus monitor per monitor (3 on desktop). Move the watcher into
a shared Gamemode singleton so only one runs regardless of screen count.

dot_config/quickshell/bar/GamemodePill.qml

@@ -1,20 +1,17 @@
 import Quickshell
-import Quickshell.Io
 import QtQuick
 import QtQuick.Layouts
 import "../shared" as Shared
 
 // Gamemode indicator — visible only when gamemode is active.
-// Event-driven: re-checks status when GameMode emits a D-Bus register/unregister
-// signal (via `gdbus monitor`), instead of polling on a timer.
+// State comes from the shared Gamemode singleton (one gdbus monitor for all
+// screens), not a per-pill process.
 BarPill {
     id: root
 
     groupName: ""          // no popout
     accentColor: Shared.Theme.green
-    visible: isActive
-
-    property bool isActive: false
+    visible: Shared.Gamemode.active
 
     content: [
         Text {
@@ -25,31 +22,4 @@ BarPill {
             font.family: Shared.Theme.iconFont
         }
     ]
-
-    Process {
-        id: gameProc
-        command: ["gamemoded", "--status"]
-        stdout: StdioCollector {
-            onStreamFinished: {
-                root.isActive = this.text.indexOf("is active") >= 0
-            }
-        }
-    }
-
-    function poll() { gameProc.running = false; gameProc.running = true; }
-
-    // Long-lived monitor on GameMode's session-bus object. Each GameRegistered /
-    // GameUnregistered signal prints a line; re-check status only then.
-    Process {
-        id: monitor
-        running: true
-        command: ["gdbus", "monitor", "-e",
-                  "-d", "com.feralinteractive.GameMode",
-                  "-o", "/com/feralinteractive/GameMode"]
-        stdout: SplitParser {
-            onRead: line => { if (line.indexOf("Registered") >= 0) root.poll() }
-        }
-    }
-
-    Component.onCompleted: root.poll()
 }

dot_config/quickshell/shared/Gamemode.qml

@@ -0,0 +1,37 @@
+pragma Singleton
+
+import Quickshell
+import Quickshell.Io
+import QtQuick
+
+// Single GameMode watcher shared by every bar instance, so only one long-lived
+// `gdbus monitor` runs regardless of how many screens exist. Event-driven:
+// re-checks status only when GameMode emits a register/unregister signal.
+Singleton {
+    id: root
+
+    property bool active: false
+
+    Process {
+        id: gameProc
+        command: ["gamemoded", "--status"]
+        stdout: StdioCollector {
+            onStreamFinished: root.active = this.text.indexOf("is active") >= 0
+        }
+    }
+
+    function poll() { gameProc.running = false; gameProc.running = true; }
+
+    Process {
+        id: monitor
+        running: true
+        command: ["gdbus", "monitor", "-e",
+                  "-d", "com.feralinteractive.GameMode",
+                  "-o", "/com/feralinteractive/GameMode"]
+        stdout: SplitParser {
+            onRead: line => { if (line.indexOf("Registered") >= 0) root.poll() }
+        }
+    }
+
+    Component.onCompleted: poll()
+}