Per [mara on PR #615 comment 7349](http://localhost:3000/hyperhive/hyperhive/pulls/615#issuecomment-7349):
> follow nix conventions, services.hyperhive it is. the earlier we
> change this, the less breakage.
Renames the entire host-side option tree under `services.hyperhive.*`:
- `services.hive-c0re.*` → `services.hyperhive.c0re.*`
- `hyperhive.enable` → `services.hyperhive.enable`
- `hyperhive.domain` → `services.hyperhive.domain`
- `hyperhive.forge.*` → `services.hyperhive.forge.*`
- `hyperhive.matrix.*` → `services.hyperhive.matrix.*`
Per mara's "earlier = less breakage", the previous `services.hive-c0re.enable`
deprecation alias is dropped. Operators get a clear eval error on the
old paths pointing at the rename. Single migration moment.
Per-agent options in `nix/templates/harness-base.nix` (`hyperhive.model`,
`hyperhive.allowedRecipients`, etc.) stay at `hyperhive.*` — they're
container-level config, not services in the NixOS sense.
Verified via `nix flake check --no-build` + an end-to-end NixOS eval
exercising every renamed path.
Follow-up needed: rust source comments referencing the old NixOS
option names (`hive-c0re/src/{meta,coordinator,main,dashboard}.rs`)
should be updated in a separate pure-rust PR to keep this one
strictly nix-only.