Add resource definitions for all 22 API tags, wire client accessors and require tree

lib/fiken/resources/activities.rb

@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module Fiken
+  module Resources
+    # /companies/{slug}/activities (time-tracking activities)
+    class Activities < Resource::Base
+      include Resource::Listable
+      include Resource::Findable
+      include Resource::Creatable
+      include Resource::PatchUpdatable
+      include Resource::Deletable
+
+      def resource_path
+        "activities"
+      end
+    end
+  end
+end