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/hypr/hyprland.conf.template

@@ -0,0 +1,18 @@
+# dots-hyprland NixOS Configuration
+# Generated from template - do not edit directly
+
+# Quickshell configuration
+$qsConfig = ii
+exec = hyprctl dispatch submap global # DO NOT REMOVE THIS OR YOU WON'T BE ABLE TO USE ANY KEYBIND
+submap = global # This is required for catchall to work
+
+# Source configuration files
+source=~/.config/hypr/env.conf
+source=~/.config/hypr/execs.conf
+source=~/.config/hypr/general.conf
+source=~/.config/hypr/rules.conf
+source=~/.config/hypr/colors.conf
+source=~/.config/hypr/keybinds.conf
+
+# Custom user overrides (if they exist)
+source=~/.config/hypr/custom.conf