Make flake self-contained - consolidate installer-replication

BREAKING CHANGE: Remove external dots-hyprland dependency

- Imported all essential configs from dots-hyprland/installer-replication
- Added complete configs/ directory with:
  - hypr/ - Hyprland configuration
  - quickshell/ - Quickshell widgets and config
  - applications/ - Application configurations
  - scripts/ - Utility scripts
  - matugen/ - Material You theming
- Updated flake.nix to use local ./configs instead of external repo
- Simplified update-flake script (removed external repo management)
- Updated README to reflect self-contained architecture
- All builds pass with local configurations

Benefits:
- No external repository dependencies
- Faster builds (no network dependencies)
- Version controlled configs in single repo
- Easier maintenance and development
- Complete installer replication in one place

configs/quickshell/modules/common/widgets/NotificationAppIcon.qml

@@ -0,0 +1,103 @@
+import qs.modules.common
+import "./notification_utils.js" as NotificationUtils
+import Qt5Compat.GraphicalEffects
+import QtQuick
+import Quickshell
+import Quickshell.Widgets
+import Quickshell.Services.Notifications
+
+Rectangle { // App icon
+    id: root
+    property var appIcon: ""
+    property var summary: ""
+    property var urgency: NotificationUrgency.Normal
+    property var image: ""
+    property real scale: 1
+    property real size: 45 * scale
+    property real materialIconScale: 0.57
+    property real appIconScale: 0.7
+    property real smallAppIconScale: 0.49
+    property real materialIconSize: size * materialIconScale
+    property real appIconSize: size * appIconScale
+    property real smallAppIconSize: size * smallAppIconScale
+
+    implicitWidth: size
+    implicitHeight: size
+    radius: Appearance.rounding.full
+    color: Appearance.colors.colSecondaryContainer
+    Loader {
+        id: materialSymbolLoader
+        active: root.appIcon == ""
+        anchors.fill: parent
+        sourceComponent: MaterialSymbol {
+            text: {
+                const defaultIcon = NotificationUtils.findSuitableMaterialSymbol("")
+                const guessedIcon = NotificationUtils.findSuitableMaterialSymbol(root.summary)
+                return (root.urgency == NotificationUrgency.Critical && guessedIcon === defaultIcon) ?
+                    "release_alert" : guessedIcon
+            }
+            anchors.fill: parent
+            color: (root.urgency == NotificationUrgency.Critical) ? 
+                ColorUtils.mix(Appearance.m3colors.m3onSecondary, Appearance.m3colors.m3onSecondaryContainer, 0.1) :
+                Appearance.m3colors.m3onSecondaryContainer
+            iconSize: root.materialIconSize
+            horizontalAlignment: Text.AlignHCenter
+            verticalAlignment: Text.AlignVCenter
+        }
+    }
+    Loader {
+        id: appIconLoader
+        active: root.image == "" && root.appIcon != ""
+        anchors.centerIn: parent
+        sourceComponent: IconImage {
+            id: appIconImage
+            implicitSize: root.appIconSize
+            asynchronous: true
+            source: Quickshell.iconPath(root.appIcon, "image-missing")
+        }
+    }
+    Loader {
+        id: notifImageLoader
+        active: root.image != ""
+        anchors.fill: parent
+        sourceComponent: Item {
+            anchors.fill: parent
+            Image {
+                id: notifImage
+                anchors.fill: parent
+                readonly property int size: parent.width
+
+                source: root.image
+                fillMode: Image.PreserveAspectCrop
+                cache: false
+                antialiasing: true
+                asynchronous: true
+
+                width: size
+                height: size
+                sourceSize.width: size
+                sourceSize.height: size
+
+                layer.enabled: true
+                layer.effect: OpacityMask {
+                    maskSource: Rectangle {
+                        width: notifImage.size
+                        height: notifImage.size
+                        radius: Appearance.rounding.full
+                    }
+                }
+            }
+            Loader {
+                id: notifImageAppIconLoader
+                active: root.appIcon != ""
+                anchors.bottom: parent.bottom
+                anchors.right: parent.right
+                sourceComponent: IconImage {
+                    implicitSize: root.smallAppIconSize
+                    asynchronous: true
+                    source: Quickshell.iconPath(root.appIcon, "image-missing")
+                }
+            }
+        }
+    }
+}