Address code review comments for configuration documentation

This commit addresses all 8 code review comments on the configuration
simplification PR, improving documentation clarity and adding comprehensive
testing guidance.

## Documentation Improvements

- Fix: Changed "Deprecated:" to "Renamed to:" in configuration-deprecated.md
  for better clarity
- Add: Filename heading for /config/shakapacker.yml in Prerequisites section
- Add: Migration note in configuration-pro.md explaining Pro docs will be
  consolidated in future PR

## Testing Configuration Enhancements

- Enhance: Completely rewrote build_test_command section in configuration.md
  - Clarified the two approaches are mutually exclusive
  - Added clear pros/cons for each approach
  - Provided detailed examples for both methods
  - Linked to comprehensive testing guide

- NEW: Created comprehensive testing configuration guide
  (docs/guides/testing-configuration.md)
  - 390 lines of detailed guidance
  - Covers both Shakapacker auto-compilation and React on Rails test helper
  - Migration guides between approaches
  - Troubleshooting section
  - Performance considerations
  - CI/CD guidance
  - Decision matrix for choosing approaches

## Generator Template Updates

- Update: Commented out build_test_command in generator template by default
  - Recommends simpler Shakapacker compile: true approach
  - Provides clear alternative with test helper for advanced users
  - Links to comprehensive testing guide
  - Prevents confusion for new users

## Doctor Program Enhancements

- NEW: Added check_server_bundle_prerender_consistency() to doctor.rb
  - Detects when prerender is enabled but server_bundle_js_file not configured
  - Detects when server_bundle_js_file is set but prerender never used
  - Scans view files for prerender: true usage
  - Provides actionable recommendations

- NEW: Added check_build_test_configuration() to doctor.rb
  - Detects conflicting test asset compilation configurations
  - Checks for both compile: true and build_test_command being set
  - Validates alignment between config and test helpers
  - Detects missing test asset compilation setup
  - Links to testing configuration guide

## Files Changed

- docs/api-reference/configuration-deprecated.md
- docs/api-reference/configuration-pro.md
- docs/api-reference/configuration.md
- docs/guides/testing-configuration.md (NEW)
- lib/generators/react_on_rails/templates/base/base/config/initializers/react_on_rails.rb.tt
- lib/react_on_rails/doctor.rb

All changes pass RuboCop and Prettier validation.

Addresses comments: #1 (not applicable), #2, #3, #4, #5, #6, #7, #8, #9

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

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

Author: justin808

docs/api-reference/configuration-deprecated.md

@@ -31,7 +31,7 @@ See [CHANGELOG.md](../CHANGELOG.md) for details.
 **Default:** `false`
 **Status:** ⚠️ DEPRECATED
 
-**Deprecated:** Use `generated_component_packs_loading_strategy = :defer` instead.
+**Renamed to:** `generated_component_packs_loading_strategy = :defer`
 
 **Migration:**
 

docs/api-reference/configuration-pro.md

@@ -11,6 +11,8 @@ React Server Components and Streaming SSR are React on Rails Pro features.
 For detailed configuration of RSC and streaming features, see the Pro package documentation:
 [react_on_rails_pro/docs/configuration.md](https://github.com/shakacode/react_on_rails/blob/master/react_on_rails_pro/docs/configuration.md)
 
+> **Note:** The Pro documentation is currently maintained separately in the `react_on_rails_pro` directory. We plan to migrate and consolidate Pro documentation into the main docs structure in a future PR for better discoverability and consistency.
+
 ### Key Pro Configurations
 
 These options are configured in the `ReactOnRailsPro.configure` block:

docs/api-reference/configuration.md

@@ -10,6 +10,8 @@ See [Essential Configuration](#essential-configuration) below for the minimal co
 
 ## Prerequisites
 
+### `/config/shakapacker.yml`
+
 First, you should have a `/config/shakapacker.yml` setup.
 
 Here is the setup when using the recommended `/` directory for your `node_modules` and source files:
@@ -115,21 +117,60 @@ Note: There should be ONE server bundle that can render all your server-rendered
 **Default:** `""`
 **Used with:** `ReactOnRails::TestHelper.configure_rspec_to_compile_assets(config)`
 
-**Note:** It's generally preferred to set `compile: true` in your `config/shakapacker.yml` for the test environment instead of using this configuration option. Use this option only if you need to customize the build command or want explicit control over test asset compilation.
+**Important:** This option is only needed if you're using the React on Rails test helper. The two approaches below are **mutually exclusive** - use one or the other, not both.
+
+#### Recommended Approach: Shakapacker Auto-Compilation
+
+Set `compile: true` in `config/shakapacker.yml` for the test environment. Shakapacker will automatically compile assets before running tests:
+
+```yaml
+test:
+  compile: true
+  public_output_path: webpack/test
+```
+
+**Pros:**
+
+- Simpler configuration (no extra setup in spec helpers)
+- Managed by Shakapacker directly
+- Automatically integrates with Rails test environment
+
+**Cons:**
 
-The command to run to build webpack assets during test runs:
+- Less explicit control over when compilation happens
+- May compile more often than necessary
+
+#### Alternative Approach: React on Rails Test Helper
+
+Use `build_test_command` with `ReactOnRails::TestHelper.configure_rspec_to_compile_assets(config)` if you need explicit control:
 
 ```ruby
+# config/initializers/react_on_rails.rb
 config.build_test_command = "RAILS_ENV=test bin/shakapacker"
 ```
 
-**Preferred alternative:** Set `compile: true` in `config/shakapacker.yml`:
+```ruby
+# spec/rails_helper.rb (or spec_helper.rb)
+require "react_on_rails/test_helper"
 
-```yaml
-test:
-  compile: true
+RSpec.configure do |config|
+  ReactOnRails::TestHelper.configure_rspec_to_compile_assets(config)
+end
 ```
 
+**Pros:**
+
+- Explicit control over compilation timing
+- Only compiles once before test suite runs
+- Can customize the build command
+
+**Cons:**
+
+- Requires additional setup in spec helpers
+- More configuration to maintain
+
+For more details on testing configuration, see the [Testing Configuration Guide](../guides/testing-configuration.md).
+
 ## File-Based Component Registry
 
 If you have many components and want to avoid manually managing webpack entry points for each one, React on Rails can automatically generate component packs based on your file system structure. This feature is particularly useful for large applications with dozens of components.