Refactor email delivery and background jobs system

- Switch from SolidQueue to async job processor for simpler background job handling
- Remove SolidQueue gem and related configuration files
- Add letter_opener gem for development email preview
- Fix invitation email template issues (invitation_login_token method and route helper)
- Configure SMTP settings via environment variables in application.rb
- Add email delivery configuration banner on admin users page
- Improve admin users page with inline action buttons and SMTP configuration warnings
- Update development and production environments to use async processor
- Add helper methods to detect SMTP configuration and filter out localhost settings

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

config/application.rb

@@ -23,5 +23,18 @@ module Clinch
     #
     # config.time_zone = "Central Time (US & Canada)"
     # config.eager_load_paths << Rails.root.join("extras")
+
+      # Configure SMTP settings using environment variables
+    config.action_mailer.delivery_method = :smtp
+    config.action_mailer.smtp_settings = {
+      address: ENV.fetch('SMTP_ADDRESS', 'localhost'),
+      port: ENV.fetch('SMTP_PORT', 587),
+      domain: ENV.fetch('SMTP_DOMAIN', 'localhost'),
+      user_name: ENV.fetch('SMTP_USER_NAME', nil),
+      password: ENV.fetch('SMTP_PASSWORD', nil),
+      authentication: ENV.fetch('SMTP_AUTHENTICATION', 'plain').to_sym,
+      enable_starttls_auto: ENV.fetch('SMTP_STARTTLS_AUTO', 'true') == 'true',
+      openssl_verify_mode: OpenSSL::SSL::VERIFY_PEER
+    }
   end
 end

config/environments/development.rb

@@ -31,8 +31,9 @@ Rails.application.configure do
   # Store uploaded files on the local file system (see config/storage.yml for options).
   config.active_storage.service = :local
 
-  # Don't care if the mailer can't send.
-  config.action_mailer.raise_delivery_errors = false
+  # Preview emails in browser using letter_opener
+  config.action_mailer.delivery_method = :letter_opener
+  config.action_mailer.perform_deliveries = true
 
   # Make template changes take effect immediately.
   config.action_mailer.perform_caching = false
@@ -58,9 +59,8 @@ Rails.application.configure do
   # Highlight code that enqueued background job in logs.
   config.active_job.verbose_enqueue_logs = true
 
-  # Use Solid Queue for background jobs (same as production).
-  config.active_job.queue_adapter = :solid_queue
-  config.solid_queue.connects_to = { database: { writing: :queue } }
+  # Use async processor for background jobs in development
+  config.active_job.queue_adapter = :async
   
 
   # Highlight code that triggered redirect in logs.

config/environments/production.rb

@@ -49,9 +49,8 @@ Rails.application.configure do
   # Replace the default in-process memory cache store with a durable alternative.
   config.cache_store = :solid_cache_store
 
-  # Replace the default in-process and non-durable queuing backend for Active Job.
-  config.active_job.queue_adapter = :solid_queue
-  config.solid_queue.connects_to = { database: { writing: :queue } }
+  # Use async processor for background jobs (modify as needed for production)
+  config.active_job.queue_adapter = :async
 
   # Ignore bad email addresses and do not raise email delivery errors.
   # Set this to true and configure the email server for immediate delivery to raise delivery errors.

config/puma.rb

@@ -34,8 +34,7 @@ port ENV.fetch("PORT", 3000)
 # Allow puma to be restarted by `bin/rails restart` command.
 plugin :tmp_restart
 
-# Run the Solid Queue supervisor inside of Puma for single-server deployments.
-plugin :solid_queue if ENV["SOLID_QUEUE_IN_PUMA"]
+# Solid Queue plugin removed - now using async processor
 
 # Specify the PID file. Defaults to tmp/pids/server.pid in development.
 # In other environments, only set the PID file if requested.

config/recurring.yml

@@ -1,15 +0,0 @@
-# examples:
-#   periodic_cleanup:
-#     class: CleanSoftDeletedRecordsJob
-#     queue: background
-#     args: [ 1000, { batch_size: 500 } ]
-#     schedule: every hour
-#   periodic_cleanup_with_command:
-#     command: "SoftDeletedRecord.due.delete_all"
-#     priority: 2
-#     schedule: at 5am every day
-
-production:
-  clear_solid_queue_finished_jobs:
-    command: "SolidQueue::Job.clear_finished_in_batches(sleep_between_batches: 0.3)"
-    schedule: every hour at minute 12