services.hyperhive.swarm.* used to carry both swarm-wide facts (name,
domain, hives, ca) and the 'does THIS host run it' toggles for every
swarm service. deploy.nix already split those toggles out into their
own services.hyperhive.deploy.* namespace; this is the docs-side
follow-up now that swarm.* is genuinely swarm-wide-only.
nix/docs/default.nix: host.md drops the swarm/deploy subtrees
(builtins.removeAttrs on the already-picked host tree, not
lib.recursiveUpdate -- that merges rather than deletes, which would
have silently kept them on host.md); swarm.md and deploy.md are new
markdown pages, each its own pickSubtrees root. nix/packages/default.nix
exposes docs-swarm/docs-deploy as flake outputs alongside the existing
docs-host/docs-agent. docs/gotchas.md's Nix options reference section
and docs/swarm/README.md get pointers to the new split.