Replace Docker Swarm with custom orchestrator

[bohdan-shulha]

Docker Swarm shows itself as not a production-grade system, despite all the "extremely stable and easy to use" (c) Mirantis speeches, it has already completely failed to start containers after the machine was restarted, twice. The networking is also not the strongest side of Swarm (remember DIRD which we had to include in our solution to be able to handle web analytics?). Or Docker Swarm networking layer running just before any user-defined iptables rule is applied, and incompatible with easy-to-use tools like ufw?

Just for no reason.

It resolves by itself in a few hours consuming all the CPU it finds along the way.

Swarm meant to be "lightweight k8s", but you can't pretend to this title if the primary function of the software is not functioning well.

The scope of this task includes whipping out the Docker Swarm and replacing it with a hand-crafted solution, which will orchestrate containers for us, just much like Andras did with Coolify or DHH with Kamal.

To simplify the implementation, we might make the "placement node ID" required at this moment and later extend it with auto-balancing/running on nodes with specific labels/etc.