feat: Add Amazon SES inbound email support (#12893)

## Summary
- add AWS ActionMailbox SES gems
- document SES as incoming email provider
- note SES option in configuration

## Testing
- `bundle exec rubocop config/initializers/mailer.rb
config/environments/production.rb Gemfile`


------
[Codex
Task](https://chatgpt.com/codex/tasks/task_e_68bbb7d482288326b8f04bb795af0322)

---------

Co-authored-by: Pranav <pranav@chatwoot.com>
Co-authored-by: Vinay Keerthi <11478411+stonecharioteer@users.noreply.github.com>

Gemfile

@@ -55,6 +55,9 @@ gem 'azure-storage-blob', git: 'https://github.com/chatwoot/azure-storage-ruby',
 gem 'google-cloud-storage', '>= 1.48.0', require: false
 gem 'image_processing'
 
+##-- for actionmailbox --##
+gem 'aws-actionmailbox-ses', '~> 0'
+
 ##-- gems for database --#
 gem 'groupdate'
 gem 'pg'