[lib] update processDMOpsActionType to handle outboundP2PMessages

Summary:
ENG-8423.

We need to process DM Operations and save OutboundP2PMessages in DB in the same SQL transaction to handle cases when the app crashes after applying changes to our store and before addressing messages to other peers - this is inconsistency from which we're unable to heal.

Depends on D13146

Test Plan:
Tested in next diff.

Note: This stack is tested end-to-end according to the process described here.

Reviewers: tomek, inka

Reviewed By: tomek

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D13148