Fix test mocks to support stream.closed? checks

Commit 0815ce0 added stream.closed? checks to prevent wasted work after
client disconnect, but the test mocks didn't stub this method, causing
all streaming tests to fail with:

  #<InstanceDouble(ActionController::Live::Buffer)> received unexpected
  message :closed? with (no args)

Changes:
- Stub .closed? to return false in helper_spec.rb test setup
- Stub .closed? to return false in stream_spec.rb setup_stream_test
- Update spec/dummy/Gemfile.lock to include async gem dependencies
  (needed when running bundle install in spec/dummy directory)

This fixes 14 failing tests:
- 10 failures in react_on_rails_pro_helper_spec.rb
- 4 failures in stream_spec.rb

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: ihabadham

react_on_rails_pro/spec/dummy/Gemfile.lock

@@ -22,6 +22,7 @@ PATH
   specs:
     react_on_rails_pro (16.2.0.beta.4)
       addressable
+      async (>= 2.6)
       connection_pool
       execjs (~> 2.9)
       httpx (~> 1.5)
@@ -107,6 +108,12 @@ GEM
       public_suffix (>= 2.0.2, < 7.0)
     amazing_print (1.6.0)
     ast (2.4.2)
+    async (2.34.0)
+      console (~> 1.29)
+      fiber-annotation
+      io-event (~> 1.11)
+      metrics (~> 0.12)
+      traces (~> 0.18)
     base64 (0.2.0)
     benchmark (0.4.0)
     bigdecimal (3.1.9)
@@ -131,6 +138,10 @@ GEM
     coderay (1.1.3)
     concurrent-ruby (1.3.5)
     connection_pool (2.5.0)
+    console (1.34.2)
+      fiber-annotation
+      fiber-local (~> 1.1)
+      json
     coveralls (0.8.23)
       json (>= 1.8, < 3)
       simplecov (~> 0.16.1)
@@ -165,6 +176,9 @@ GEM
     ffi (1.17.0-x86_64-darwin)
     ffi (1.17.0-x86_64-linux-gnu)
     ffi (1.17.0-x86_64-linux-musl)
+    fiber-annotation (0.2.0)
+    fiber-local (1.1.0)
+      fiber-storage
     fiber-storage (1.0.0)
     generator_spec (0.10.0)
       activesupport (>= 3.0.0)
@@ -184,6 +198,7 @@ GEM
     i18n (1.14.7)
       concurrent-ruby (~> 1.0)
     io-console (0.8.0)
+    io-event (1.14.0)
     irb (1.15.1)
       pp (>= 0.6.0)
       rdoc (>= 4.0.0)
@@ -216,6 +231,7 @@ GEM
     marcel (1.0.4)
     matrix (0.4.2)
     method_source (1.1.0)
+    metrics (0.15.0)
     mini_mime (1.1.5)
     mini_portile2 (2.8.8)
     minitest (5.25.4)
@@ -447,6 +463,7 @@ GEM
     tins (1.33.0)
       bigdecimal
       sync
+    traces (0.18.2)
     turbolinks (5.2.1)
       turbolinks-source (~> 5.2)
     turbolinks-source (5.2.0)

react_on_rails_pro/spec/dummy/spec/helpers/react_on_rails_pro_helper_spec.rb

@@ -443,6 +443,7 @@ def mock_request_and_response(mock_chunks = chunks, count: 1)
           written_chunks << chunk
         end
         allow(mocked_stream).to receive(:close)
+        allow(mocked_stream).to receive(:closed?).and_return(false)
         mocked_response = instance_double(ActionDispatch::Response)
         allow(mocked_response).to receive(:stream).and_return(mocked_stream)
         allow(self).to receive(:response).and_return(mocked_response)
@@ -583,6 +584,7 @@ def execute_stream_view_containing_react_components
         written_chunks.clear
         allow(mocked_stream).to receive(:write) { |chunk| written_chunks << chunk }
         allow(mocked_stream).to receive(:close)
+        allow(mocked_stream).to receive(:closed?).and_return(false)
         mocked_response = instance_double(ActionDispatch::Response)
         allow(mocked_response).to receive(:stream).and_return(mocked_stream)
         allow(self).to receive(:response).and_return(mocked_response)

react_on_rails_pro/spec/react_on_rails_pro/stream_spec.rb

@@ -388,6 +388,7 @@ def setup_stream_test(component_count: 2)
       allow(mocked_response).to receive(:stream).and_return(mocked_stream)
       allow(mocked_stream).to receive(:write)
       allow(mocked_stream).to receive(:close)
+      allow(mocked_stream).to receive(:closed?).and_return(false)
       allow(controller).to receive(:response).and_return(mocked_response)
 
       [component_queues, controller, mocked_stream]