activitywatch: simple symlinkJoin wrapper

pkgs/applications/office/activitywatch/wrapper.nix

···
+{ lib
+, symlinkJoin
+, aw-server-rust
+, aw-qt
+, aw-watcher-afk
+, aw-watcher-window
+, extraWatchers ? [ ]
+}:
+
+symlinkJoin {
+  name = "activitywatch-${aw-server-rust.version}";
+  paths = [
+    aw-server-rust.out
+    aw-qt.out
+    aw-watcher-afk.out
+    aw-watcher-window.out
+  ] ++ (lib.forEach extraWatchers (p: p.out));
+}

pkgs/top-level/all-packages.nix

···
     aw-watcher-afk
     aw-watcher-window;
 
+  activitywatch = callPackage ../applications/office/activitywatch/wrapper.nix { };
+
   adobe-reader = pkgsi686Linux.callPackage ../applications/misc/adobe-reader { };
 
   adl = callPackage ../applications/video/adl { };