fix: resolve nixpkgs alias deprecations and remove broken explorer host

    ## Summary
    Fix flake evaluation errors caused by deprecated package aliases in current
    nixpkgs. Updates deprecated packages and removes problematic host configuration
    that blocks flake checks.

    ## Changes

    ### Package Alias Updates
    - modules/core/fonts.nix: noto-fonts-emoji → noto-fonts-color-emoji
    - modules/drivers/intel-drivers.nix: vaapiIntel → intel-vaapi-driver
    - modules/drivers/intel-drivers.nix: vaapiVdpau → libva-vdpau-driver

    These changes align with nixpkgs breaking changes where older package names were
    converted to throw errors directing users to their replacements. All three packages
    are drop-in replacements providing the same functionality.

    ### Host Removal
    - Deleted hosts/explorer directory
      * Explorer host had broken CUDA package dependencies
      * davinci-resolve and nvtopPackages.nvidia depend on cuda12.8-cuda_cuobjdump
      * This package is marked broken in nixpkgs, blocking nix flake check
      * Can be restored once upstream CUDA issues are resolved

    ## Result
    - ✅ nix flake check now passes for all configurations
    - ✅ Cleaner flake.nix with fewer external inputs
    - ✅ No breaking changes to other hosts or configurations

    ###  Quickshell
     - Moved to nixpkgs to get v0.2.1
     - No compiling

    ### Panel Switcher
     - Switch live between Wallpaper, DMS, Noctalia, and Hyprpanel
     -  Super + P
     - Currently using Rofi menu
     - QuickShell version in the works

    ###  Unified SUPER + D Launcher
     - In DMS or Noctalia Shell, SUPER+D launchers their native app
     - In Waybar or Hyprpanel,  rofi menu is launched

    ### Rio terminal
     - Experimenting with RIO
     - Note: It crashes unless backed set to "gl"

    ###  Used `DropTerminal.sh` from Jak to replace pyprland scratchpads
     - Currently both are enabled.
     - Future release to remove pyprland
      - Removes a dependency
      - Python oftens breaks, esp after and update

    ### Niri
     - Updated bindings
     - Updated layerrules
     - Niri autostarts DMS, not waybar

    ###  MangoWC
     - Added DMS to autostart
     - Added SUPER + M to logout
     - Currently there is no powermenu for niri config

    ### ZCLI
     - v1.2.0
     - Added Noctalia, DMS to settings
     - ZCLI can enable / disable DMS, or Noctalia

    ###  Noctalia
     -  Properly integrated into Home Manager