Update gem dependencies to use pessimistic version constraints for better compatibility

Author: crmne

ruby_llm.gemspec

@@ -35,9 +35,9 @@ Gem::Specification.new do |spec|
   spec.require_paths = ['lib']
 
   # Runtime dependencies
-  spec.add_dependency 'event_stream_parser', '>= 0.3.0', '< 2.0.0'
-  spec.add_dependency 'faraday', '>= 2.0'
-  spec.add_dependency 'faraday-multipart', '>= 1.0'
-  spec.add_dependency 'faraday-retry', '>= 2.0'
-  spec.add_dependency 'zeitwerk', '>= 2.6'
+  spec.add_dependency 'event_stream_parser', '~> 1'
+  spec.add_dependency 'faraday', '~> 2'
+  spec.add_dependency 'faraday-multipart', '~> 1'
+  spec.add_dependency 'faraday-retry', '~> 2'
+  spec.add_dependency 'zeitwerk', '~> 2'
 end