We should check whether the IDs are thick - it protects us against an attacker who could try to create operations referencing thin thread entities.

https://linear.app/comm/issue/ENG-9826/validate-the-ids-from-the-dm-operations

Depends on D13848

Tested a couple of scenarios:

• sending a text message
• changing thread settings
• editing a message
• reacting to a message
• creating a sidebar

In the cases where another message was a target, tested that it works for both text and edit thread settings messages.