Address CodeRabbit review feedback

- Move Rails environment loading inside run_precompile_tasks to improve
  startup time for help/kill commands (saves 1-3 seconds)
- Remove unused HMR=true from Procfile.dev wp-server process
  (webpack config only checks WEBPACK_DEV_SERVER, not HMR env var)

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

Author: justin808

Procfile.dev

@@ -11,4 +11,4 @@ rails: bundle exec thrust bin/rails server -p 3000
 # Client webpack dev server with HMR
 wp-client: RAILS_ENV=development NODE_ENV=development bin/shakapacker-dev-server
 # Server webpack watcher for SSR bundle
-wp-server: HMR=true SERVER_BUNDLE_ONLY=yes bin/shakapacker --watch
+wp-server: SERVER_BUNDLE_ONLY=yes bin/shakapacker --watch

bin/dev

@@ -26,11 +26,13 @@
 
 require "bundler/setup"
 require "react_on_rails/dev"
-require_relative "../config/environment"
 
 # Run precompile tasks before starting development server
 # This ensures rescript and locale files are generated before webpack starts
 def run_precompile_tasks
+  # Load Rails environment only when needed (saves 1-3s for help/kill commands)
+  require_relative "../config/environment"
+
   puts "📦 Running precompile tasks..."
 
   # Build ReScript files first