Covers the Block deploy on missing required env vars guardrail end to
end: deploy a Postgres stack with a required password, enable the
guardrail, watch a real update get refused with a named-variable
message, fix it, and verify from the Activity and Environment tabs.
Adds the Tutorials tab to docs.json with 15 stub pages across three
groups (Fleet & nodes, Deploy & automate, Secure & integrate), and
writes the first full tutorial: enrolling a remote node via Pilot
Agent mode, verified end to end against a live control instance and
a second host running an existing Jellyfin Compose stack.
SaelixCode