feat: a bunch of misc updates

nixos/droidcam.nix

@@ -0,0 +1,26 @@
+# /etc/nixos/configuration.nix
+{ config, pkgs, ... }:
+
+{
+  # Virtual cam settings: see https://wiki.nixos.org/wiki/OBS_Studio#Using_the_Virtual_Camera
+  boot.extraModulePackages = with config.boot.kernelPackages; [
+    v4l2loopback
+  ];
+  boot.extraModprobeConfig = ''
+    options v4l2loopback devices=1 video_nr=1 card_label="OBS Cam" exclusive_caps=1
+  '';
+  security.polkit.enable = true;
+
+  # Install OBS Studio with droidcam-obs
+  users.users.foo = {
+    packages = with pkgs; [
+      # ...
+      (wrapOBS {
+        plugins = with obs-studio-plugins; [
+          droidcam-obs
+        ];
+      })
+      # ...
+    ];
+  };
+}