[2.16.0] Consolidate DHH styles and add /feature-video command

- Merge dhh-ruby-style into dhh-rails-style for comprehensive Rails conventions
- Add testing.md reference covering Rails testing patterns
- Add /feature-video command for recording PR demo videos
- Update docs and component counts

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

plugins/compound-engineering/skills/dhh-rails-style/references/testing.md

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+# Testing - DHH Rails Style
+
+## Core Philosophy
+
+"Minitest with fixtures - simple, fast, deterministic." The approach prioritizes pragmatism over convention.
+
+## Why Minitest Over RSpec
+
+- **Simpler**: Less DSL magic, plain Ruby assertions
+- **Ships with Rails**: No additional dependencies
+- **Faster boot times**: Less overhead
+- **Plain Ruby**: No specialized syntax to learn
+
+## Fixtures as Test Data
+
+Rather than factories, fixtures provide preloaded data:
+- Loaded once, reused across tests
+- No runtime object creation overhead
+- Explicit relationship visibility
+- Deterministic IDs for easier debugging
+
+### Fixture Structure
+```yaml
+# test/fixtures/users.yml
+david:
+  identity: david
+  account: basecamp
+  role: admin
+
+jason:
+  identity: jason
+  account: basecamp
+  role: member
+
+# test/fixtures/rooms.yml
+watercooler:
+  name: Water Cooler
+  creator: david
+  direct: false
+
+# test/fixtures/messages.yml
+greeting:
+  body: Hello everyone!
+  room: watercooler
+  creator: david
+```
+
+### Using Fixtures in Tests
+```ruby
+test "sending a message" do
+  user = users(:david)
+  room = rooms(:watercooler)
+
+  # Test with fixture data
+end
+```
+
+### Dynamic Fixture Values
+ERB enables time-sensitive data:
+```yaml
+recent_card:
+  title: Recent Card
+  created_at: <%= 1.hour.ago %>
+
+old_card:
+  title: Old Card
+  created_at: <%= 1.month.ago %>
+```
+
+## Test Organization
+
+### Unit Tests
+Verify business logic using setup blocks and standard assertions:
+
+```ruby
+class CardTest < ActiveSupport::TestCase
+  setup do
+    @card = cards(:one)
+    @user = users(:david)
+  end
+
+  test "closing a card creates a closure" do
+    assert_difference -> { Card::Closure.count } do
+      @card.close(creator: @user)
+    end
+
+    assert @card.closed?
+    assert_equal @user, @card.closure.creator
+  end
+
+  test "reopening a card destroys the closure" do
+    @card.close(creator: @user)
+
+    assert_difference -> { Card::Closure.count }, -1 do
+      @card.reopen
+    end
+
+    refute @card.closed?
+  end
+end
+```
+
+### Integration Tests
+Test full request/response cycles:
+
+```ruby
+class CardsControllerTest < ActionDispatch::IntegrationTest
+  setup do
+    @user = users(:david)
+    sign_in @user
+  end
+
+  test "closing a card" do
+    card = cards(:one)
+
+    post card_closure_path(card)
+
+    assert_response :success
+    assert card.reload.closed?
+  end
+
+  test "unauthorized user cannot close card" do
+    sign_in users(:guest)
+    card = cards(:one)
+
+    post card_closure_path(card)
+
+    assert_response :forbidden
+    refute card.reload.closed?
+  end
+end
+```
+
+### System Tests
+Browser-based tests using Capybara:
+
+```ruby
+class MessagesTest < ApplicationSystemTestCase
+  test "sending a message" do
+    sign_in users(:david)
+    visit room_path(rooms(:watercooler))
+
+    fill_in "Message", with: "Hello, world!"
+    click_button "Send"
+
+    assert_text "Hello, world!"
+  end
+
+  test "editing own message" do
+    sign_in users(:david)
+    visit room_path(rooms(:watercooler))
+
+    within "#message_#{messages(:greeting).id}" do
+      click_on "Edit"
+    end
+
+    fill_in "Message", with: "Updated message"
+    click_button "Save"
+
+    assert_text "Updated message"
+  end
+
+  test "drag and drop card to new column" do
+    sign_in users(:david)
+    visit board_path(boards(:main))
+
+    card = find("#card_#{cards(:one).id}")
+    target = find("#column_#{columns(:done).id}")
+
+    card.drag_to target
+
+    assert_selector "#column_#{columns(:done).id} #card_#{cards(:one).id}"
+  end
+end
+```
+
+## Advanced Patterns
+
+### Time Testing
+Use `travel_to` for deterministic time-dependent assertions:
+
+```ruby
+test "card expires after 30 days" do
+  card = cards(:one)
+
+  travel_to 31.days.from_now do
+    assert card.expired?
+  end
+end
+```
+
+### External API Testing with VCR
+Record and replay HTTP interactions:
+
+```ruby
+test "fetches user data from API" do
+  VCR.use_cassette("user_api") do
+    user_data = ExternalApi.fetch_user(123)
+
+    assert_equal "John", user_data[:name]
+  end
+end
+```
+
+### Background Job Testing
+Assert job enqueueing and email delivery:
+
+```ruby
+test "closing card enqueues notification job" do
+  card = cards(:one)
+
+  assert_enqueued_with(job: NotifyWatchersJob, args: [card]) do
+    card.close
+  end
+end
+
+test "welcome email is sent on signup" do
+  assert_emails 1 do
+    Identity.create!(email: "new@example.com")
+  end
+end
+```
+
+### Testing Turbo Streams
+```ruby
+test "message creation broadcasts to room" do
+  room = rooms(:watercooler)
+
+  assert_turbo_stream_broadcasts [room, :messages] do
+    room.messages.create!(body: "Test", creator: users(:david))
+  end
+end
+```
+
+## Testing Principles
+
+### 1. Test Observable Behavior
+Focus on what the code does, not how it does it:
+
+```ruby
+# ❌ Testing implementation
+test "calls notify method on each watcher" do
+  card.expects(:notify).times(3)
+  card.close
+end
+
+# ✅ Testing behavior
+test "watchers receive notifications when card closes" do
+  assert_difference -> { Notification.count }, 3 do
+    card.close
+  end
+end
+```
+
+### 2. Don't Mock Everything
+
+```ruby
+# ❌ Over-mocked test
+test "sending message" do
+  room = mock("room")
+  user = mock("user")
+  message = mock("message")
+
+  room.expects(:messages).returns(stub(create!: message))
+  message.expects(:broadcast_create)
+
+  MessagesController.new.create
+end
+
+# ✅ Test the real thing
+test "sending message" do
+  sign_in users(:david)
+  post room_messages_url(rooms(:watercooler)),
+    params: { message: { body: "Hello" } }
+
+  assert_response :success
+  assert Message.exists?(body: "Hello")
+end
+```
+
+### 3. Tests Ship with Features
+Same commit, not TDD-first but together. Neither before (strict TDD) nor after (deferred testing).
+
+### 4. Security Fixes Always Include Regression Tests
+Every security fix must include a test that would have caught the vulnerability.
+
+### 5. Integration Tests Validate Complete Workflows
+Don't just test individual pieces - test that they work together.
+
+## File Organization
+
+```
+test/
+├── controllers/         # Integration tests for controllers
+├── fixtures/           # YAML fixtures for all models
+├── helpers/            # Helper method tests
+├── integration/        # API integration tests
+├── jobs/               # Background job tests
+├── mailers/            # Mailer tests
+├── models/             # Unit tests for models
+├── system/             # Browser-based system tests
+└── test_helper.rb      # Test configuration
+```
+
+## Test Helper Setup
+
+```ruby
+# test/test_helper.rb
+ENV["RAILS_ENV"] ||= "test"
+require_relative "../config/environment"
+require "rails/test_help"
+
+class ActiveSupport::TestCase
+  fixtures :all
+
+  parallelize(workers: :number_of_processors)
+end
+
+class ActionDispatch::IntegrationTest
+  include SignInHelper
+end
+
+class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
+  driven_by :selenium, using: :headless_chrome
+end
+```
+
+## Sign In Helper
+
+```ruby
+# test/support/sign_in_helper.rb
+module SignInHelper
+  def sign_in(user)
+    session = user.identity.sessions.create!
+    cookies.signed[:session_id] = session.id
+  end
+end
+```