Remove unmaintained syslog-logger dependency

The syslog-logger gem hasn't been updated since 2014 and is unnecessary.
The steno syslog sink only used it as a thin wrapper around the base
syslog gem. Refactored to use syslog directly:

- Use Syslog.open() directly instead of Syslog::Logger.new()
- Update tests to use Syslog.close if Syslog.opened?
- Remove syslog-logger from dependencies
- Update CHANGELOG to reflect removal

This reduces dependencies and removes reliance on an unmaintained gem
while maintaining identical functionality.

Author: johha

CHANGELOG.md

@@ -12,10 +12,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Updated development dependencies to latest versions
 - Added GitHub Actions for CI/CD
 - CI now tests all Ruby versions independently (fail-fast: false)
+- Refactored syslog sink to use syslog gem directly instead of unmaintained syslog-logger
 
 ### Added
 - Automated testing on multiple Ruby versions (3.0, 3.1, 3.2, 3.3, 3.4)
-- Ruby 3.4 compatibility: added syslog and syslog-logger gem dependencies for non-Windows platforms
+- Ruby 3.4 compatibility: added syslog gem dependency for non-Windows platforms
 - Dependabot configuration for automated dependency updates
 - GitHub Actions release workflow for automatic gem publishing
 - Release documentation (RELEASING.md)

lib/steno/sink/syslog.rb

@@ -2,7 +2,7 @@
   require 'steno/sink/base'
 
   require 'singleton'
-  require 'syslog/logger'
+  require 'syslog'
 
   class Steno::Sink::Syslog < Steno::Sink::Base
     include Singleton
@@ -29,9 +29,7 @@ def initialize
 
     def open(identity)
       @identity = identity
-
-      Syslog::Logger.new(@identity)
-      @syslog = Syslog::Logger.syslog
+      @syslog = Syslog.open(@identity, Syslog::LOG_PID | Syslog::LOG_CONS)
     end
 
     def add_record(record)

spec/unit/sink/syslog_spec.rb

@@ -16,7 +16,7 @@
 
     describe '#add_record' do
       after do
-        Syslog::Logger.syslog = nil
+        Syslog.close if Syslog.opened?
       end
 
       it 'appends an encoded record with the correct priority' do

steno.gemspec

@@ -34,10 +34,7 @@ Gem::Specification.new do |gem|
   gem.add_development_dependency('rubocop-rake', '~> 0.6')
   gem.add_development_dependency('rubocop-rspec', '~> 3.0')
 
-  unless RUBY_PLATFORM =~ /mswin|mingw|cygwin/
-    gem.add_dependency('syslog')
-    gem.add_dependency('syslog-logger')
-  end
+  gem.add_dependency('syslog') unless RUBY_PLATFORM =~ /mswin|mingw|cygwin/
 
   if RUBY_PLATFORM =~ /mswin|mingw|cygwin/
     gem.platform = Gem::Platform::CURRENT