Fix EventMachine test pollution causing cascade failures

- Add after(:example) hook to clear stale realtime_clients and stop
  EM reactor between tests, preventing leaked state from crashed or
  timed-out tests poisoning subsequent EM-dependent tests
- Switch paginated result specs from manual include + run_reactor to
  :event_machine metadata tag so they get proper before/around/after
  lifecycle hooks

Author: matt423

spec/support/event_machine_helper.rb

@@ -139,6 +139,21 @@ def wait_until(condition_block, &block)
     # Ensure EventMachine shutdown hooks are deregistered for every test
     EventMachine.instance_variable_set '@tails', []
   end
+
+  # Catch-all cleanup for ANY test that used EventMachine, whether via
+  # the :event_machine tag or by calling run_reactor directly. Without this,
+  # a crashed/timed-out reactor and stale client references leak into
+  # subsequent tests causing cascade failures.
+  config.after(:example) do
+    RSpec::EventMachine.realtime_clients.clear
+    begin
+      EventMachine.stop if EventMachine.reactor_running?
+    rescue RuntimeError
+      # EM can be in a corrupted state (e.g. signal_loopbreak failure)
+      # where reactor_running? returns true but stop raises. Swallow
+      # the error to prevent cascading failures across subsequent tests.
+    end
+  end
 end
 
 module RSpec

spec/unit/models/http_paginated_result_spec.rb

@@ -128,40 +128,32 @@
     end
 
     if defined?(Ably::Realtime)
-      context 'with option async_blocking_operations: true' do
-        include RSpec::EventMachine
-
+      context 'with option async_blocking_operations: true', :event_machine do
         subject do
           paginated_result_class.new(http_response, full_url, paged_client, async_blocking_operations: true)
         end
 
         context '#next' do
           it 'returns a SafeDeferrable that catches exceptions in callbacks and logs them' do
-            run_reactor do
-              expect(subject.next).to be_a(Ably::Util::SafeDeferrable)
-              stop_reactor
-            end
+            expect(subject.next).to be_a(Ably::Util::SafeDeferrable)
+            stop_reactor
           end
 
           it 'allows a success callback block to be added' do
-            run_reactor do
-              subject.next do |paginated_result|
-                expect(paginated_result).to be_a(Ably::Models::HttpPaginatedResponse)
-                stop_reactor
-              end
+            subject.next do |paginated_result|
+              expect(paginated_result).to be_a(Ably::Models::HttpPaginatedResponse)
+              stop_reactor
             end
           end
         end
 
         context '#first' do
           it 'calls the errback callback when first page headers are missing' do
-            run_reactor do
-              subject.next do |paginated_result|
-                deferrable = subject.first
-                deferrable.errback do |error|
-                  expect(error).to be_a(Ably::Exceptions::PageMissing)
-                  stop_reactor
-                end
+            subject.next do |paginated_result|
+              deferrable = subject.first
+              deferrable.errback do |error|
+                expect(error).to be_a(Ably::Exceptions::PageMissing)
+                stop_reactor
               end
             end
           end

spec/unit/models/paginated_result_spec.rb

@@ -126,40 +126,32 @@
     end
 
     if defined?(Ably::Realtime)
-      context 'with option async_blocking_operations: true' do
-        include RSpec::EventMachine
-
+      context 'with option async_blocking_operations: true', :event_machine do
         subject do
           paginated_result_class.new(http_response, full_url, paged_client, async_blocking_operations: true)
         end
 
         context '#next' do
           it 'returns a SafeDeferrable that catches exceptions in callbacks and logs them' do
-            run_reactor do
-              expect(subject.next).to be_a(Ably::Util::SafeDeferrable)
-              stop_reactor
-            end
+            expect(subject.next).to be_a(Ably::Util::SafeDeferrable)
+            stop_reactor
           end
 
           it 'allows a success callback block to be added' do
-            run_reactor do
-              subject.next do |paginated_result|
-                expect(paginated_result).to be_a(Ably::Models::PaginatedResult)
-                stop_reactor
-              end
+            subject.next do |paginated_result|
+              expect(paginated_result).to be_a(Ably::Models::PaginatedResult)
+              stop_reactor
             end
           end
         end
 
         context '#first' do
           it 'calls the errback callback when first page headers are missing' do
-            run_reactor do
-              subject.next do |paginated_result|
-                deferrable = subject.first
-                deferrable.errback do |error|
-                  expect(error).to be_a(Ably::Exceptions::PageMissing)
-                  stop_reactor
-                end
+            subject.next do |paginated_result|
+              deferrable = subject.first
+              deferrable.errback do |error|
+                expect(error).to be_a(Ably::Exceptions::PageMissing)
+                stop_reactor
               end
             end
           end