After running a 2 node Proxmox cluster for the longest time I've finally purchased a Zimaboard single board x86_64 computer to add as a 3rd node in order to test the HA features.
After installing the latest Proxmox 8.0.4 to an external SSD connected with the included SATA cable to the Zimaboard, I added my new node to the cluster. I installed a Debian12 LXC container and Docker inside that one. Then I installed Gitea through Docker and finally migrated my repos from a Debian10 LXC, I had running on another node, to the Debian12 I created.
Everything went smoothly, along with the Proxmox upgrade from 7 to 8 on my two other nodes. The only issue I faced was the NFS shares I have on my 2nd node needed a config update to include the new node IP as an accepted client.
Running a full 3 node cluster at home with such low power consumption is a truly amazing, silent and space-saving endeavor.