Add new server modules and configurations for various services

- Introduced `default-creds` module for managing default credentials with Umami integration.
- Added `fail2ban` module for brute-force attack protection with configurable ban times.
- Created `firewall` module to enable and configure basic firewall settings.
- Implemented `gitea` module for self-hosted Git service with PostgreSQL backend.
- Developed `glance` module for a customizable dashboard with various widgets and themes.
- Added `iknowyou` module for a self-hosted password manager with production and demo environments.
- Introduced `kernel-hardening` module for enhancing kernel security settings.
- Created `mazanoke` module for a simple web application with Nginx integration.
- Added `mealie` module for a self-hosted meal planning application.
- Implemented `stirling-pdf` module for PDF generation service.
- Developed `umami` module for self-hosted analytics with secret management.
- Added `ssh` module for secure SSH configuration with user restrictions.
- Introduced `nixy` theme for a customized aesthetic experience across services.

nixos/audio.nix

@@ -0,0 +1,23 @@
+# Audio configuration for NixOS using PipeWire
+{
+  security.rtkit.enable = true;
+  services.pulseaudio.enable = false;
+
+  services.pipewire = {
+    enable = true;
+    alsa.enable = true;
+    alsa.support32Bit = true;
+    pulse.enable = true;
+    jack.enable = true;
+    wireplumber = {
+      enable = true;
+      extraConfig = {
+        "10-disable-camera" = {
+          "wireplumber.profiles" = {
+            main."monitor.libcamera" = "disabled";
+          };
+        };
+      };
+    };
+  };
+}