Add pagination to admin pages

app/controllers/admin/donations_controller.rb

@@ -5,7 +5,8 @@ class Admin::DonationsController < Admin::BaseController
   # GET /donations
   # GET /donations.json
   def index
-    @donations = Donation.all.order('created_at desc')
+    @pagy, @donations = pagy(Donation.all.order('created_at desc'))
+
     @stats = {
       overall_sats: @donations.all.sum("amount_sats"),
       donor_count: Donation.distinct.count(:user_id)

app/controllers/admin/invitations_controller.rb

@@ -1,7 +1,8 @@
 class Admin::InvitationsController < Admin::BaseController
   def index
     @current_section = :invitations
-    @invitations_used = Invitation.used.order('used_at desc')
+    @pagy, @invitations_used = pagy(Invitation.used.order('used_at desc'))
+
     @stats = {
       available: Invitation.unused.count,
       accepted: @invitations_used.length,

app/controllers/admin/users_controller.rb

@@ -6,7 +6,7 @@ class Admin::UsersController < Admin::BaseController
     ldap   = LdapService.new
     @ou    = params[:ou] || "kosmos.org"
     @orgs  = ldap.fetch_organizations
-    @users = User.where(ou: @ou).order(cn: :asc).to_a
+    @pagy, @users = pagy(User.where(ou: @ou).order(cn: :asc))
 
     @stats = {
       users_confirmed: User.where(ou: @ou).confirmed.count,