Add Noctalia shell with Quickshell overview

- Add `noctalia` input to flake and lock it in `flake.lock`.
- Include `noctalia` and `quickshell` modules in `flake.nix`.
- Extend core packages to accept `inputs` and `system`; add
  `quickshell.nix`
  with required Qt6 packages and environment variables.
- Enable `upower` service for battery handling.
- Add home modules `noctalia.nix` and `overview.nix` (QML UI, README,
  assets, widgets, services) to provide a workspace overview.
- Comment out unused rofi and web‑search binds; update `exec‑once` to
  start
  the overview daemon and `noctalia-shell`.
- Provide `restart.noctalia` script and its Nix wrapper.
- Enable `noctalia-shell` in `stylix` configuration.

modules/home/overview/common/widgets/StyledToolTip.qml

@@ -0,0 +1,23 @@
+import QtQuick
+import QtQuick.Controls
+import "."
+
+ToolTip {
+    id: root
+    property bool extraVisibleCondition: true
+    property bool alternativeVisibleCondition: false
+    readonly property bool internalVisibleCondition: (extraVisibleCondition && (parent.hovered === undefined || parent?.hovered)) || alternativeVisibleCondition
+    verticalPadding: 5
+    horizontalPadding: 10
+    background: null
+
+    visible: internalVisibleCondition
+    
+    contentItem: StyledToolTipContent {
+        id: contentItem
+        text: root.text
+        shown: root.internalVisibleCondition
+        horizontalPadding: root.horizontalPadding
+        verticalPadding: root.verticalPadding
+    }
+}