fix: respect isEncrypted:false if supplied in notify: command, and ensure the correct value is always transmitted onwards

[gkc]

- What I did fix: respect isEncrypted:false if supplied in notify: command, and ensure the correct value is always transmitted onwards

Addresses at_server parts of #1944

- How I did it See commits

- How to verify it

• [x] at_server automated tests pass
• [ ] manually verify that at_client_sdk e2e tests pass when running against this branch's version of atServer
• [x] manually verify that noports e2e tests pass when running against this branch's version of atServer