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/services/FirstRunExperience.qml

@@ -0,0 +1,43 @@
+pragma Singleton
+
+import qs.modules.common
+import qs.modules.common.functions
+import Quickshell
+import Quickshell.Io
+
+Singleton {
+    id: root
+    property string firstRunFilePath: `${Directories.state}/user/first_run.txt`
+    property string firstRunFileContent: "This file is just here to confirm you've been greeted :>"
+    property string firstRunNotifSummary: "Welcome!"
+    property string firstRunNotifBody: "Hit Super+/ for a list of keybinds"
+    property string defaultWallpaperPath: FileUtils.trimFileProtocol(`${Directories.assetsPath}/images/default_wallpaper.png`)
+    property string welcomeQmlPath: FileUtils.trimFileProtocol(Quickshell.shellPath("welcome.qml"))
+
+    function load() {
+        firstRunFileView.reload()
+    }
+
+    function enableNextTime() {
+        Quickshell.execDetached(["rm", "-f", root.firstRunFilePath])
+    }
+    function disableNextTime() {
+        Quickshell.execDetached(["bash", "-c", `echo '${root.firstRunFileContent}' > '${root.firstRunFilePath}'`])
+    }
+
+    function handleFirstRun() {
+        Quickshell.execDetached([Directories.wallpaperSwitchScriptPath, root.defaultWallpaperPath])
+        Quickshell.execDetached(["bash", "-c", `qs -p '${root.welcomeQmlPath}'`])
+    }
+
+    FileView {
+        id: firstRunFileView
+        path: Qt.resolvedUrl(firstRunFilePath)
+        onLoadFailed: (error) => {
+            if (error == FileViewError.FileNotFound) {
+                firstRunFileView.setText(root.firstRunFileContent)
+                root.handleFirstRun()
+            }
+        }
+    }
+}