Add linting, formatting, and CI with fixes for all warnings

Infrastructure:
- Add deadnix, nixfmt, and statix to flake inputs
- Add formatter output to flake for nix fmt support
- Add deadnix, nixfmt, statix to Home Manager packages
- Add GitHub Actions workflow for CI validation
- Add .pre-commit-config.yaml with hooks for nixfmt, deadnix, and statix
- Support x86_64-darwin in formatter

Statix fixes (W10/W20 warnings):
- Remove unused lambda argument from nixpkgs-settings.nix
- Merge repeated keys in hardware-configuration.nix files (boot.initrd, boot, fileSystems)
- Merge repeated keys in nixnuc/default.nix (services, virtualisation)
- Merge repeated keys in rainbow-planet/default.nix (desktopManager)
- Merge repeated keys in home/general/default.nix (home)

Deadnix fixes (unused declarations):
- Remove unused pkgs/lib/username/http_port arguments from various files
- Fix unused final parameter in overlay functions (final -> _final)

CI/pre-commit fixes:
- Fix pre-commit statix config: add pass_filenames: false
- Fix CI workflow: use nix run nixpkgs# prefix and --ci flag for nixfmt

modules/shared/home/linux/apps/hexchat.nix

@@ -1,3 +1,3 @@
-{ ... }: {
+{
   programs.hexchat.enable = true;
 }

modules/shared/home/linux/apps/pidgin.nix

@@ -1,3 +1,3 @@
-{ ... }: {
+{
   programs.pidgin.enable = true;
 }

modules/shared/home/linux/apps/tilix.nix

@@ -1,4 +1,6 @@
-{ lib, pkgs, ... }: with lib.hm.gvariant; {
+{ lib, pkgs, ... }:
+with lib.hm.gvariant;
+{
 
   dconf.settings = {
     "com/gexperts/Tilix/profiles/2b7c4080-0ddd-46c5-8f23-563fd3ba789d" = {
@@ -10,7 +12,24 @@
       font = "Hack Nerd Font Mono 12";
       foreground-color = "#F8F8F2";
       highlight-colors-set = false;
-      palette = [ "#272822" "#F92672" "#A6E22E" "#F4BF75" "#66D9EF" "#AE81FF" "#A1EFE4" "#F8F8F2" "#75715E" "#F92672" "#A6E22E" "#F4BF75" "#66D9EF" "#AE81FF" "#A1EFE4" "#F9F8F5" ];
+      palette = [
+        "#272822"
+        "#F92672"
+        "#A6E22E"
+        "#F4BF75"
+        "#66D9EF"
+        "#AE81FF"
+        "#A1EFE4"
+        "#F8F8F2"
+        "#75715E"
+        "#F92672"
+        "#A6E22E"
+        "#F4BF75"
+        "#66D9EF"
+        "#AE81FF"
+        "#A1EFE4"
+        "#F9F8F5"
+      ];
       use-system-font = false;
       use-theme-colors = false;
       visible-name = "Default";
@@ -20,11 +39,13 @@
 
   home.file = {
     ".config/tilix/schemes/Beanbag-Mathias.json".source = ../../../files/tilix/Beanbag-Mathias.json;
-    ".config/tilix/schemes/Catppuccin-Frappe.json".source = (pkgs.fetchFromGitHub {
-      owner = "catppuccin";
-      repo = "tilix";
-      rev = "3fd05e03419321f2f2a6aad6da733b28be1765ef";
-      hash = "sha256-SI7QxQ+WBHzeuXbTye+s8pi4tDVZOV4Aa33mRYO276k=";
-    } + "/src/Catppuccin-Frappe.json");
+    ".config/tilix/schemes/Catppuccin-Frappe.json".source =
+      pkgs.fetchFromGitHub {
+        owner = "catppuccin";
+        repo = "tilix";
+        rev = "3fd05e03419321f2f2a6aad6da733b28be1765ef";
+        hash = "sha256-SI7QxQ+WBHzeuXbTye+s8pi4tDVZOV4Aa33mRYO276k=";
+      }
+      + "/src/Catppuccin-Frappe.json";
   };
-}
+}

modules/shared/home/linux/apps/waybar.nix

@@ -1,17 +1,20 @@
-{ pkgs, ... }: {
+{ pkgs, ... }:
+{
   home.file = {
     ".config/waybar/config".source = ../../../files/waybar/config;
-    ".config/waybar/frappe.css".source = (pkgs.fetchFromGitHub {
-      owner = "catppuccin";
-      repo = "waybar";
-      rev = "f74ab1eecf2dcaf22569b396eed53b2b2fbe8aff";
-      hash = "sha256-WLJMA2X20E5PCPg0ZPtSop0bfmu+pLImP9t8A8V4QK8=";
-    } + "/themes/frappe.css");
+    ".config/waybar/frappe.css".source =
+      pkgs.fetchFromGitHub {
+        owner = "catppuccin";
+        repo = "waybar";
+        rev = "f74ab1eecf2dcaf22569b396eed53b2b2fbe8aff";
+        hash = "sha256-WLJMA2X20E5PCPg0ZPtSop0bfmu+pLImP9t8A8V4QK8=";
+      }
+      + "/themes/frappe.css";
     ".config/waybar/style.css".source = ../../../files/waybar/style.css;
   };
 
-   programs = {
+  programs = {
     # Using file in ../../files/waybar/ to configure waybar
     waybar.enable = true;
   };
-}
+}

modules/shared/home/linux/apps/xfce4-terminal.nix

@@ -1,4 +1,4 @@
-{ ... }: {
+{
   home.file = {
     ".config/xfce4/terminal/accels.scm".source = ../../../files/xfce4/terminal/accels.scm;
   };
@@ -11,7 +11,8 @@
       "color-background" = "#08052b";
       "color-cursor" = "#ff7f7f";
       "color-cursor-use-default" = false;
-      "color-palette" = "#000000;#e52222;#a6e32d;#fc951e;#c48dff;#fa2573;#67d9f0;#f2f2f2;#555555;#ff5555;#55ff55;#ffff55;#5555ff;#ff55ff;#55ffff;#ffffff";
+      "color-palette" =
+        "#000000;#e52222;#a6e32d;#fc951e;#c48dff;#fa2573;#67d9f0;#f2f2f2;#555555;#ff5555;#55ff55;#ffff55;#5555ff;#ff55ff;#55ffff;#ffffff";
       "font-name" = "Hack Nerd Font Mono 12";
       "misc-always-show-tabs" = false;
       "misc-bell" = false;
@@ -43,4 +44,4 @@
       "title-initial" = "xfce4-terminal";
     };
   };
-}
+}