Refine documentation and test structure per code review

Addresses additional code review suggestions:

1. Edge Case Documentation:
   - Added @note about manual ENV variable setting
   - Documented use case for debugging/setup scenarios
   - Warned against bypassing validation in production

2. Improved Test Structure:
   - Refactored precedence tests to use nested contexts
   - Changed structure: "with other skip conditions also present"
     -> "when package.json exists and ARGV indicates generator"
     -> "when package.json is missing"
   - More descriptive test names focusing on behavior
   - Better organization showing ENV precedence clearly

3. Simplified Comments:
   - Reduced redundancy in install_generator.rb ensure block
   - Changed from 2 lines to 1 concise line
   - Removed redundant statement about concurrent generators

Changes maintain all functionality while improving readability
and addressing edge cases in documentation.

All specs pass (21 examples, 0 failures)
RuboCop clean

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

Co-Authored-By: Claude <[email protected]>

Author: justin808

lib/generators/react_on_rails/install_generator.rb

@@ -73,8 +73,7 @@ def run_generators
           GeneratorMessages.add_error(error)
         end
       ensure
-        # Always clean up ENV variable to avoid affecting subsequent processes
-        # This is safe even if concurrent generators run in separate processes
+        # Always clean up ENV variable, even if generator fails
         ENV.delete("REACT_ON_RAILS_SKIP_VALIDATION")
         print_generator_messages
       end

lib/react_on_rails/engine.rb

@@ -29,6 +29,12 @@ class Engine < ::Rails::Engine
     #   run in a single process, so concurrent execution is not a concern. If running
     #   generators concurrently (e.g., in parallel tests), ensure tests run in separate
     #   processes to avoid ENV variable conflicts.
+    #
+    # @note Manual ENV Setting: While this ENV variable is designed to be set by generators,
+    #   users can manually set it (e.g., `REACT_ON_RAILS_SKIP_VALIDATION=true rails server`)
+    #   to bypass validation. This should only be done temporarily during debugging or
+    #   setup scenarios. The validation helps catch version mismatches early, so bypassing
+    #   it in production is not recommended.
     def self.skip_version_validation?
       # Skip if explicitly disabled via environment variable (set by generators)
       # Using ENV variable instead of ARGV because Rails can modify/clear ARGV during

spec/react_on_rails/engine_spec.rb

@@ -32,40 +32,42 @@ module ReactOnRails
             .with("[React on Rails] Skipping validation - disabled via environment variable")
         end
 
-        context "with package.json present and ARGV set to generator" do
-          before do
-            allow(File).to receive(:exist?).with(package_json_path).and_return(true)
-            stub_const("ARGV", ["generate", "react_on_rails:install"])
-          end
+        context "with other skip conditions also present" do
+          context "when package.json exists and ARGV indicates generator" do
+            before do
+              allow(File).to receive(:exist?).with(package_json_path).and_return(true)
+              stub_const("ARGV", ["generate", "react_on_rails:install"])
+            end
 
-          it "returns true (ENV takes precedence over other conditions)" do
-            expect(described_class.skip_version_validation?).to be true
-          end
+            it "prioritizes ENV over ARGV check" do
+              expect(described_class.skip_version_validation?).to be true
+            end
 
-          it "logs ENV variable message, not ARGV message" do
-            described_class.skip_version_validation?
-            expect(Rails.logger).to have_received(:debug)
-              .with("[React on Rails] Skipping validation - disabled via environment variable")
-            expect(Rails.logger).not_to have_received(:debug)
-              .with("[React on Rails] Skipping validation during generator runtime")
+            it "short-circuits before checking ARGV" do
+              described_class.skip_version_validation?
+              expect(Rails.logger).to have_received(:debug)
+                .with("[React on Rails] Skipping validation - disabled via environment variable")
+              expect(Rails.logger).not_to have_received(:debug)
+                .with("[React on Rails] Skipping validation during generator runtime")
+            end
           end
-        end
 
-        context "with package.json missing" do
-          before do
-            allow(File).to receive(:exist?).with(package_json_path).and_return(false)
-          end
+          context "when package.json is missing" do
+            before do
+              allow(File).to receive(:exist?).with(package_json_path).and_return(false)
+            end
 
-          it "returns true (ENV takes precedence over package.json check)" do
-            expect(described_class.skip_version_validation?).to be true
-          end
+            it "prioritizes ENV over package.json check" do
+              expect(described_class.skip_version_validation?).to be true
+            end
 
-          it "logs ENV variable message, not package.json message" do
-            described_class.skip_version_validation?
-            expect(Rails.logger).to have_received(:debug)
-              .with("[React on Rails] Skipping validation - disabled via environment variable")
-            expect(Rails.logger).not_to have_received(:debug)
-              .with("[React on Rails] Skipping validation - package.json not found")
+            it "short-circuits before checking package.json" do
+              described_class.skip_version_validation?
+              expect(Rails.logger).to have_received(:debug)
+                .with("[React on Rails] Skipping validation - disabled via environment variable")
+              expect(Rails.logger).not_to have_received(:debug)
+                .with("[React on Rails] Skipping validation - package.json not found")
+            end
           end
         end
       end