nixos/trilium-server: add option for environment file

The server component of trilium allows for OAuth to be configured.
Ideally secrets shouldn't be loaded in the nix store so this would allow
for an environment file to be passed in via sops/agenix/ect

nixos/modules/services/web-apps/trilium.nix

@@ -41,6 +41,16 @@ in
       '';
     };
 
+    environmentFile = mkOption {
+      type = types.nullOr types.path;
+      default = null;
+      example = "/secrets/trilium.env";
+      description = ''
+        File to load as the environment file. This allows you to pass secrets in without writing
+        to the nix store.
+      '';
+    };
+
     instanceName = mkOption {
       type = types.str;
       default = "Trilium";
@@ -126,6 +136,7 @@ in
           environment.TRILIUM_DATA_DIR = cfg.dataDir;
           serviceConfig = {
             ExecStart = lib.getExe cfg.package;
+            EnvironmentFile = cfg.environmentFile;
             User = "trilium";
             Group = "trilium";
             PrivateTmp = "true";