Add type column to _pico_peer_address

Summary

This patch introduces connection_type column in the table _pico_peer_address.

In _pico_peer_address information about the address and port from pgproto is inserted during cluster bootstrap, and when a new instance joins the cluster.

• Close #1237 (closed)
• Cherry-pick to: none
• Docs follow-up: docs#468 (closed)
• Changelog is updated

Closes #1237 (closed)