refine: improve generator output to be more Rails-like

- Simplify initializer template to show only essential providers
- Update post-install message to focus on community support
- Remove business promotion from generator output
- Add GitHub star option as free way to support

Author: crmne

lib/generators/ruby_llm/install_generator.rb

@@ -112,8 +112,8 @@ def show_install_info
       say "\n  📚 Full docs: https://rubyllm.com", :cyan
 
       say "\n  ❤️  Love RubyLLM?", :magenta
-      say '     • Sponsor: https://github.com/sponsors/crmne'
-      say '     • Try Chat with Work: https://chatwithwork.com'
+      say '     • ⭐ Star on GitHub: https://github.com/crmne/ruby_llm'
+      say '     • 💖 Sponsor: https://github.com/sponsors/crmne'
       say "\n"
     end
   end

spec/lib/generators/ruby_llm/install_generator_spec.rb

@@ -162,7 +162,7 @@
     end
 
     it 'includes sponsorship information' do
-      expect(generator_content).to include('https://github.com/sponsors/crmne').and include('https://chatwithwork.com')
+      expect(generator_content).to include('https://github.com/sponsors/crmne').and include('Star on GitHub')
     end
   end