[#75314] Replace deprecated Pagy max_pages option

Pagy 43.4.3 deprecated `:max_pages` and recommends capping records
before pagination instead. Caps the combined array in `base_journals`.

https://community.openproject.org/wp/75314

app/services/work_packages/activities_tab/paginator.rb

@@ -52,6 +52,8 @@ class WorkPackages::ActivitiesTab::Paginator
   include Pagy::Method
   include WorkPackages::ActivitiesTab::JournalSortingInquirable
 
+  MAX_PAGES = 100
+
   def self.paginate(work_package, params = {})
     new(work_package, params).call
   end
@@ -72,7 +74,7 @@ class WorkPackages::ActivitiesTab::Paginator
         @filter = :all # Ignore filter when jumping to specific journal
         pagy_array_for_target_journal(anchor_type, target_record_id)
       else
-        pagy(:offset, base_journals, **pagy_options)
+        pagy(:offset, capped_journals, **pagy_options)
       end
 
     # For UI display: if user wants "oldest first" UI, reverse the array
@@ -87,7 +89,6 @@ class WorkPackages::ActivitiesTab::Paginator
     {
       page: params[:page] || 1,
       limit: params[:limit] || Pagy::DEFAULT[:limit],
-      max_pages: 100,
       request: { params: }
     }.compact
   end
@@ -127,6 +128,11 @@ class WorkPackages::ActivitiesTab::Paginator
     combine_and_sort_records(fetch_journals, fetch_revisions)
   end
 
+  def capped_journals
+    max_records = (params[:limit] || Pagy::DEFAULT[:limit]) * MAX_PAGES
+    base_journals.first(max_records)
+  end
+
   def fetch_journals
     API::V3::Activities::ActivityEagerLoadingWrapper.wrap(fetch_ar_journals)
   end

spec/services/work_packages/activities_tab/paginator_spec.rb

@@ -206,6 +206,47 @@ RSpec.describe WorkPackages::ActivitiesTab::Paginator, with_settings: { journal_
       end
     end
 
+    context "when record count exceeds MAX_PAGES cap" do
+      let(:test_limit) { 2 }
+
+      before do
+        stub_const("#{described_class}::MAX_PAGES", 3)
+        8.times do |i|
+          create(:work_package_journal, user:, notes: "Comment #{i + 1}", journable: work_package, version: i + 2)
+        end
+        params[:limit] = test_limit
+      end
+
+      it "caps total records to limit * MAX_PAGES" do
+        pagy, _records = paginator.call
+
+        expect(pagy.count).to eq(test_limit * 3)
+        expect(pagy.pages).to eq(3)
+      end
+
+      it "keeps the newest records when truncating" do
+        _pagy, records = paginator.call
+
+        notes = records.map(&:notes)
+        expect(notes).to include("Comment 8")
+        expect(notes).not_to include("Comment 1")
+      end
+
+      it "still resolves an anchor to a journal beyond the cap" do
+        oldest_journal = work_package.journals.order(:version).first
+        params[:anchor] = "comment-#{oldest_journal.id}"
+        pagy, records = paginator.call
+
+        expect(records.map(&:id)).to include(oldest_journal.id)
+
+        aggregate_failures "breaks out of capped limit" do
+          expect(pagy.count).to eq(work_package.journals.count)
+          expect(pagy.pages).to eq(5)
+          expect(pagy.page).to eq(5), "expected oldest journal on last page (page 5), got page #{pagy.page}"
+        end
+      end
+    end
+
     context "with internal comments filtering" do
       let!(:internal_journal) do
         create(:work_package_journal,