nixos/facter: add boot and storage detection

This adds automatic kernel module detection for boot-critical hardware:

- disk.nix: Detects and loads kernel modules for storage controllers
  Auto-detects modules for: disk controllers, storage controllers,
  and FireWire controllers (for FireWire-attached disks).
  Modules are automatically added to boot.initrd.availableKernelModules.

- keyboard.nix: Detects USB controller drivers for keyboard support
  Ensures USB HID drivers are loaded in initrd for keyboard access
  during boot (critical for LUKS password entry, etc.).

Follow up to #454237.
Part of incremental upstreaming from nixos-facter-modules.

nixos/modules/hardware/facter/default.nix

@@ -5,6 +5,8 @@
 }:
 {
   imports = [
+    ./disk.nix
+    ./keyboard.nix
     ./system.nix
   ];
 

nixos/modules/hardware/facter/disk.nix

@@ -0,0 +1,28 @@
+{ lib, config, ... }:
+let
+  facterLib = import ./lib.nix lib;
+
+  inherit (config.hardware.facter) report;
+in
+{
+  options.hardware.facter.detected.boot.disk.kernelModules = lib.mkOption {
+    type = lib.types.listOf lib.types.str;
+    default = lib.uniqueStrings (
+      facterLib.collectDrivers (
+        # A disk might be attached.
+        (report.hardware.firewire_controller or [ ])
+        # definitely important
+        ++ (report.hardware.disk or [ ])
+        ++ (report.hardware.storage_controller or [ ])
+      )
+    );
+    defaultText = "hardware dependent";
+    description = ''
+      List of kernel modules that are needed to access the disk.
+    '';
+  };
+
+  config = {
+    boot.initrd.availableKernelModules = config.hardware.facter.detected.boot.disk.kernelModules;
+  };
+}

nixos/modules/hardware/facter/keyboard.nix

@@ -0,0 +1,21 @@
+{ lib, config, ... }:
+let
+  facterLib = import ./lib.nix lib;
+
+  inherit (config.hardware.facter) report;
+in
+{
+  options.hardware.facter.detected.boot.keyboard.kernelModules = lib.mkOption {
+    type = lib.types.listOf lib.types.str;
+    default = lib.uniqueStrings (facterLib.collectDrivers (report.hardware.usb_controller or [ ]));
+    defaultText = "hardware dependent";
+    example = [ "usbhid" ];
+    description = ''
+      List of kernel modules to include in the initrd to support the keyboard.
+    '';
+  };
+
+  config = {
+    boot.initrd.availableKernelModules = config.hardware.facter.detected.boot.keyboard.kernelModules;
+  };
+}