Add request + system specs for the RSC demo

Request spec mirrors the dummy's `requests/rsc_payload_spec.rb` pattern
(NDJSON parsing, html-chunk presence). Covers:
- GET /server-components returns the demo page shell
- /rsc_payload/ServerComponentsPage streams a valid NDJSON payload
- /rsc_payload/LiveActivity streams a valid NDJSON payload

System spec covers the user-facing behaviors of the new sections:
- Page renders the four demo section headings
- ServerInfo labels appear (Platform, Architecture, Node.js, CPU Cores)
- Live Activity shows the live stats labels + initial Refresh count
- Refresh button increments the counter (RSCRoute fetch happens)
- Simulate Error → ErrorBoundary fallback → Retry recovers

Tests behaviors only — no internal state assertions, no specific values
(server time, RAM number) that would be flaky. Uses existing rails_helper
infrastructure (headless Chrome via DriverRegistration, Capybara defaults).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: ihabadham

spec/requests/server_components_spec.rb

@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+describe "Server Components" do
+  it "GET /server-components returns the demo page shell" do
+    get "/server-components"
+    expect(response).to have_http_status(:ok)
+    expect(response.body).to include("React Server Components Demo")
+  end
+
+  describe "RSC payload endpoint" do
+    def parsed_chunks
+      response.body.each_line.filter_map do |line|
+        stripped = line.strip
+        next if stripped.empty?
+
+        JSON.parse(stripped)
+      end
+    end
+
+    def expect_valid_rsc_payload
+      expect(response).to have_http_status(:ok)
+      expect(response.media_type).to eq("application/x-ndjson")
+      chunks = parsed_chunks
+      expect(chunks).not_to be_empty
+      expect(chunks.any? { |chunk| chunk.key?("html") }).to be(true)
+    end
+
+    it "streams a valid RSC payload for ServerComponentsPage" do
+      get "/rsc_payload/ServerComponentsPage", params: { props: "{}" }
+      expect_valid_rsc_payload
+    end
+
+    it "streams a valid RSC payload for LiveActivity" do
+      get "/rsc_payload/LiveActivity", params: { props: "{}" }
+      expect_valid_rsc_payload
+    end
+  end
+end

spec/system/server_components_demo_spec.rb

@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+describe "Server Components demo" do
+  before { visit "/server-components" }
+
+  it "renders the four demo sections" do
+    expect(page).to have_selector("h2", text: "Server Environment")
+    expect(page).to have_selector("h2", text: "Interactive Client Component")
+    expect(page).to have_selector("h2", text: "Live Server Activity")
+    expect(page).to have_selector("h2", text: "Streamed Comments")
+  end
+
+  it "shows server-side data in ServerInfo" do
+    expect(page).to have_content("Platform")
+    expect(page).to have_content("Architecture")
+    expect(page).to have_content("Node.js")
+    expect(page).to have_content("CPU Cores")
+  end
+
+  describe "Live Server Activity (RSCRoute)" do
+    it "shows the initial activity card with the live stats labels" do
+      expect(page).to have_content("SERVER TIME")
+      expect(page).to have_content("FREE RAM")
+      expect(page).to have_content("UPTIME (HRS)")
+      expect(page).to have_content("Refresh count: 0")
+    end
+
+    it "updates content when Refresh is clicked" do
+      click_button "Refresh"
+      expect(page).to have_content("Refresh count: 1")
+    end
+
+    it "shows the ErrorBoundary fallback when Simulate Error is clicked, then recovers on Retry" do
+      click_button "Simulate Error"
+      expect(page).to have_content("Server component fetch failed")
+
+      click_button "Retry"
+      expect(page).to have_content("SERVER TIME")
+      expect(page).to have_no_content("Server component fetch failed")
+    end
+  end
+end