StructuredTaskScope beyond toy examples: dependency-aware kernel bootstrap in modern Java

I did not start this because I wanted to write an article about StructuredTaskScope. I got there from a more annoying direction: bootstrap had stopped being a startup script. Once the kernel had a real subsystem graph — config, memory, persistence, graph, events, flow, transport — the old mental model broke down. The question was no longer "how do I start modules?" It became "what is actually allowed to start now, what must already be ready, and what happens if one piece fails halfway through?