terra: package Tome, add vivaldi + dotnet dev tools

Tome (née AudibleLibrary) is darman's own Photino/.NET desktop app, private
repo on our own gitea. Fetched as a flake input over ssh with darman's
ambient key — same mechanism as any other git input, private or not.

buildDotnetModule package: the Preact/Vite frontend (Tome.App/ClientApp)
builds as its own buildNpmPackage derivation and gets copied into the
published app's wwwroot, since upstream's in-project MSBuild npm target has
no network access in the Nix sandbox. Photino.Native's runtime deps (gtk3,
webkitgtk_4_1, libnotify) are wrapped in — confirmed via readelf/ldd that
this Photino build already targets webkit2gtk-4.1, not the now-removed 4.0.

Also added dotnet-sdk + nodejs to terra for developing Tome locally, and
vivaldi (unfree, extends the existing allowUnfreePredicate).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

services/desktop/desktop-apps.nix

@@ -1,7 +1,8 @@
-{ pkgs, lib, ... }:
+{ pkgs, lib, inputs, ... }:
 
 let
   rishot = pkgs.callPackage ../../pkgs/rishot.nix { };
+  tome = pkgs.callPackage ../../pkgs/tome.nix { src = inputs.tome; };
 in
 
 # Desktop applications for a workstation host (currently: terra). Split from
@@ -16,6 +17,7 @@ in
       "steam-unwrapped"
       "steam-run"
       "claude-code"
+      "vivaldi"
     ];
 
   programs.steam = {
@@ -32,7 +34,13 @@ in
     gitkraken
     jetbrains-toolbox
     kdePackages.dolphin
+    vivaldi
     rishot
+    tome
+
+    # Tome development (Tome.App targets net10.0; ClientApp is Preact/Vite).
+    dotnetCorePackages.sdk_10_0
+    nodejs
   ];
 
   fonts.packages = [ pkgs.nerd-fonts.departure-mono ];