Add DLQ, auto-purge, and health checks for Redis queues

Gemfile

@@ -3,11 +3,11 @@ source ENV['GEM_SOURCE'] || 'https://rubygems.org'
 gemspec
 
 # Evaluate Gemfile.local if it exists
-if File.exists? "#{__FILE__}.local"
+if File.exist? "#{__FILE__}.local"
   instance_eval(File.read("#{__FILE__}.local"))
 end
 
 # Evaluate ~/.gemfile if it exists
-if File.exists?(File.join(Dir.home, '.gemfile'))
+if File.exist?(File.join(Dir.home, '.gemfile'))
   instance_eval(File.read(File.join(Dir.home, '.gemfile')))
 end

Gemfile.lock

@@ -197,6 +197,7 @@ GEM
 PLATFORMS
   arm64-darwin-22
   arm64-darwin-23
+  arm64-darwin-25
   universal-java-11
   universal-java-17
   x86_64-darwin-22

lib/vmpooler/metrics/promstats.rb

@@ -329,6 +329,30 @@ def vmpooler_metrics_table
             buckets: REDIS_CONNECT_BUCKETS,
             docstring: 'vmpooler redis connection wait time',
             param_labels: %i[type provider]
+          },
+          vmpooler_health: {
+            mtype: M_GAUGE,
+            torun: %i[manager],
+            docstring: 'vmpooler health check metrics',
+            param_labels: %i[metric_path]
+          },
+          vmpooler_purge: {
+            mtype: M_GAUGE,
+            torun: %i[manager],
+            docstring: 'vmpooler purge metrics',
+            param_labels: %i[metric_path]
+          },
+          vmpooler_destroy: {
+            mtype: M_GAUGE,
+            torun: %i[manager],
+            docstring: 'vmpooler destroy metrics',
+            param_labels: %i[poolname]
+          },
+          vmpooler_clone: {
+            mtype: M_GAUGE,
+            torun: %i[manager],
+            docstring: 'vmpooler clone metrics',
+            param_labels: %i[poolname]
           }
         }
       end