fix: add flake.lock back and update host configs

- Added `flake.lock` to pin dependencies (nixpkgs, home-manager, nixvim, flake-utils, etc.)
- Cleaned up `.gitignore`: stop ignoring `*.lock`
- Removed unused `flake-utils.inputs.nixpkgs.follows`
- Nixstation host:
  - Removed `keychron.nix`, Wacom tablet config, and redundant session variables
  - Simplified GDM/GNOME configuration and XKB layout
  - Commented out virtualisation setup
- Common NVIDIA host config:
  - Added explicit kernel modules, parameters, blacklists, and kernel version
  - Ensured GNOME + GDM configuration present
  - Updated NVIDIA driver settings and CUDA support

hosts/Nixstation/hardware-configuration.nix

@@ -11,13 +11,14 @@
 
   boot = {
     initrd.availableKernelModules = [
-      "xhci_pci"
+      "ahci"
       "ehci_pci"
       "nvme"
-      "usbhid"
-      "usb_storage"
       "sd_mod"
-      "ahci"
+      "usb_storage"
+      "usbhid"
+      "sd_mod"
+      "xhci_pci"
     ];
     kernelParams = [ "amd_pstate=active" ];
     initrd.kernelModules = [ ];
@@ -25,27 +26,22 @@
     extraModulePackages = [ ];
   };
 
-  fileSystems = {
-    "/" = {
-      device = "/dev/disk/by-uuid/df74093a-637d-41a5-8c6a-2bf2dccc1506";
-      fsType = "btrfs";
-      options = [ "subvol=@" ];
-    };
+fileSystems."/" =
+  { device = "/dev/disk/by-uuid/07c4d31f-e1cd-4a02-8b3f-8c2bd2e0ce8d";
+    fsType = "btrfs";
+    options = [ "subvol=@" ];
+  };
 
-    "/boot" = {
-      device = "/dev/disk/by-uuid/E9BA-D1A3";
-      fsType = "vfat";
-      options = [
-        "fmask=0022"
-        "dmask=0022"
-      ];
-    };
+fileSystems."/home" =
+  { device = "/dev/disk/by-uuid/07c4d31f-e1cd-4a02-8b3f-8c2bd2e0ce8d";
+    fsType = "btrfs";
+    options = [ "subvol=@home" ];
+  };
 
-    "/mnt/hdd0" = {
-      device = "/dev/disk/by-uuid/940353dd-5774-4577-aba3-516d3f9c404d";
-      fsType = "btrfs";
-      options = [ "defaults" ];
-    };
+fileSystems."/boot" =
+  { device = "/dev/disk/by-uuid/D2EA-469F";
+    fsType = "vfat";
+    options = [ "fmask=0077" "dmask=0077" ];
   };
 
   swapDevices = [ ];
@@ -61,5 +57,4 @@
   };
 
   services.blueman.enable = true;
-
 }