fix(whatsapp): guard messageUpdate.create against missing parent message

[wahyuwidgetworks]

Description:
This PR addresses a critical issue in the messages.update handler that
caused PrismaClientValidationError and led to crash loops.

The Bug:
The messages.update handler in whatsapp.baileys.service.ts was
attempting to call prismaRepository.messageUpdate.create without
ensuring the existence of a parent Message record. When an update event
arrived for a message that was not stored in the Message table (e.g.,
ephemeral messages, old messages not synced, or deleted messages), the
messageId required for the MessageUpdate relation would be missing. This
resulted in a PrismaClientValidationError with the message "Argument
Message is missing," causing the application to crash. The previous logs
showed a misleading artifact Invalid this.cache.delete() invocation, but
the core issue was the missing Prisma relation.

The Fix:

• Guarded messageUpdate.create: Implemented a conditional check for
  the presence of message.messageId before attempting to create a
  MessageUpdate record.
• Graceful Handling: If message.messageId is missing, the system now
  logs a warning ([WIDGET-WORKS] Skipping messageUpdate.create for key
  ...: Parent message not found.) and skips the database write,
  preventing the crash.
• Annotation: Added // [WIDGET-WORKS] comments to the new guard logic
  for clarity and adherence to project conventions.

Impact:

• Eliminates the persistent PrismaClientValidationError crash loops in
  the messages.update handler.
• Ensures application stability and continued processing of message
  updates, even if the parent message is not found in the database.
• Prevents log spam related to these errors.

Additional Notes:

• The this.cache.delete() call within the messages.update handler is
  already wrapped in a try/catch block, providing a safety net for
  potential issues in cache deletion.
• task.md has been updated to reflect the completion of this fix.