add aspects/hosts/ configurations

Host-specific NixOS configurations for:
- alexandria (server)
- io (desktop)
- rotterdam (desktop)
- trantor (server, aarch64)

Each host has a main config file and _hostname/ directory
with hardware-configuration and other host-specific modules.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

aspects/hosts/_alexandria/nextcloud.nix

@@ -0,0 +1,97 @@
+{
+  lib,
+  config,
+  pkgs,
+  inputs,
+  ...
+}:
+
+let
+  utils = import ../../../utils.nix { inherit inputs lib; };
+  inherit (utils) mkNginxVHosts;
+in
+
+{
+  services = {
+    nextcloud = {
+      enable = true;
+      package = pkgs.nextcloud32;
+      datadir = "/data/nextcloud";
+      hostName = "cloud.baduhai.dev";
+      configureRedis = true;
+      https = true;
+      secretFile = config.age.secrets."nextcloud-secrets.json".path;
+      database.createLocally = true;
+      maxUploadSize = "16G";
+      extraApps = {
+        inherit (config.services.nextcloud.package.packages.apps)
+          calendar
+          contacts
+          notes
+          tasks
+          user_oidc
+          ;
+      };
+      extraAppsEnable = true;
+      caching = {
+        apcu = true;
+        redis = true;
+      };
+      settings = {
+        trusted_proxies = [ "127.0.0.1" ];
+        default_phone_region = "BR";
+        maintenance_window_start = "4";
+        allow_local_remote_servers = true;
+        enabledPreviewProviders = [
+          "OC\\Preview\\BMP"
+          "OC\\Preview\\EMF"
+          "OC\\Preview\\Font"
+          "OC\\Preview\\GIF"
+          "OC\\Preview\\HEIC"
+          "OC\\Preview\\Illustrator"
+          "OC\\Preview\\JPEG"
+          "OC\\Preview\\Krita"
+          "OC\\Preview\\MarkDown"
+          "OC\\Preview\\Movie"
+          "OC\\Preview\\MP3"
+          "OC\\Preview\\MSOffice2003"
+          "OC\\Preview\\MSOffice2007"
+          "OC\\Preview\\MSOfficeDoc"
+          "OC\\Preview\\OpenDocument"
+          "OC\\Preview\\PDF"
+          "OC\\Preview\\Photoshop"
+          "OC\\Preview\\PNG"
+          "OC\\Preview\\Postscript"
+          "OC\\Preview\\SVG"
+          "OC\\Preview\\TIFF"
+          "OC\\Preview\\TXT"
+          "OC\\Preview\\XBitmap"
+        ];
+      };
+      config = {
+        dbtype = "pgsql";
+        adminpassFile = config.age.secrets.nextcloud-adminpass.path;
+      };
+      phpOptions = {
+        "opcache.interned_strings_buffer" = "16";
+      };
+    };
+
+    nginx.virtualHosts = mkNginxVHosts {
+      domains."cloud.baduhai.dev" = { };
+    };
+  };
+
+  age.secrets = {
+    "nextcloud-secrets.json" = {
+      file = ../../../secrets/nextcloud-secrets.json.age;
+      owner = "nextcloud";
+      group = "nextcloud";
+    };
+    nextcloud-adminpass = {
+      file = ../../../secrets/nextcloud-adminpass.age;
+      owner = "nextcloud";
+      group = "nextcloud";
+    };
+  };
+}