* fix(whatsapp): update message source ID handling and improve Redis key formatting
* fix(whatsapp): prevent updating contact_inbox on identifier conflict
* fix(whatsapp): refactor conversation routing tests to use shared examples for better clarity and maintainability
* fix: enhance filename extraction for document messages with captions
* test: add specs for filename extraction from document messages with and without captions
* fix: update media URL stubbing for multiple message types in filename extraction tests