clan-cli: Add --wifi option to set wifi credentials. clan-app: Add wifi settings form to flash view

pkgs/installer/iwd.nix

@@ -0,0 +1,67 @@
+{
+  lib,
+  pkgs,
+  config,
+  ...
+}:
+
+let
+  cfg = config.clan.iwd;
+  toBase64 = (pkgs.callPackage ./base64.nix { inherit lib; }).toBase64;
+  wifi_config = password: ''
+    [Security]
+      Passphrase=${password}
+  '';
+in
+{
+  options.clan.iwd = {
+    networks = lib.mkOption {
+      type = lib.types.attrsOf (
+        lib.types.submodule (
+          { name, ... }:
+          {
+            options = {
+              ssid = lib.mkOption {
+                type = lib.types.strMatching "^[a-zA-Z0-9._-]+$";
+                default = name;
+                description = "The name of the wifi network";
+              };
+              password = lib.mkOption {
+                type = lib.types.str;
+                description = "The password of the wifi network";
+              };
+            };
+          }
+        )
+      );
+      default = { };
+      description = "Wifi networks to predefine";
+    };
+  };
+  config = lib.mkMerge [
+    (lib.mkIf (cfg.networks != { }) {
+      # Systemd tmpfiles rule to create /var/lib/iwd/example.psk file
+      systemd.tmpfiles.rules = lib.mapAttrsToList (
+        _: value:
+        "f+~ /var/lib/iwd/${value.ssid}.psk 0600 root root - ${toBase64 (wifi_config value.password)}"
+      ) cfg.networks;
+
+    })
+    {
+      # disable wpa supplicant
+      networking.wireless.enable = false;
+
+      # Use iwd instead of wpa_supplicant. It has a user friendly CLI
+      networking.wireless.iwd = {
+        enable = true;
+        settings = {
+          Network = {
+            EnableIPv6 = true;
+            RoutePriorityOffset = 300;
+          };
+          Settings.AutoConnect = true;
+        };
+      };
+    }
+  ];
+}