Add Omarchy shell plugin for the Stream Deck

QML bar widget + popout panel (dev.woodard.streamdeck) that drives
streamdeck-ctl: key grid shaped by the connected model, per-key editor,
brightness slider, and daemon controls. Themed via qs.Commons.

Makefile gains build-ctl, install-ctl, install-plugin, validate-plugin
and uninstall-plugin targets.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BjuZBBfzXqZgxRhxzJvkkC

omarchy-plugin/StreamDeckIcon.qml

@@ -0,0 +1,52 @@
+import QtQuick
+import qs.Commons
+
+// A 3x2 grid of keys, drawn rather than glyphed so it scales cleanly and takes
+// its colour straight from the caller (and therefore from the active theme).
+Item {
+  id: root
+
+  property real iconSize: Style.space(14)
+  property color color: Color.foreground
+  // Lit keys are drawn filled; the rest are outlined. The panel uses this to
+  // show the deck's state at a glance without a second icon.
+  property int litKeys: 6
+
+  implicitWidth: iconSize
+  implicitHeight: iconSize
+
+  readonly property int cols: 3
+  readonly property int rows: 2
+  readonly property real gap: Math.max(1, iconSize * 0.1)
+  readonly property real cell: (iconSize - gap * (cols - 1)) / cols
+  readonly property real cellHeight: (iconSize * 0.72 - gap * (rows - 1)) / rows
+
+  Item {
+    anchors.centerIn: parent
+    width: root.iconSize
+    height: root.cellHeight * root.rows + root.gap * (root.rows - 1)
+
+    Repeater {
+      model: root.cols * root.rows
+
+      Rectangle {
+        required property int index
+
+        readonly property int column: index % root.cols
+        readonly property int row: Math.floor(index / root.cols)
+        readonly property bool lit: index < root.litKeys
+
+        x: column * (root.cell + root.gap)
+        y: row * (root.cellHeight + root.gap)
+        width: root.cell
+        height: root.cellHeight
+        radius: Style.cornerRadius > 0 ? Math.max(1, root.cell * 0.22) : 0
+
+        color: lit ? root.color : "transparent"
+        border.width: lit ? 0 : Math.max(1, Math.round(root.iconSize * 0.07))
+        border.color: root.color
+        opacity: lit ? 1.0 : 0.45
+      }
+    }
+  }
+}