tailscale serve set-config now also accepts the legacy raw ipn.ServeConfig
format (as emitted by `tailscale serve status --json` and consumed via
TS_SERVE_CONFIG, which has no "version" field), so the common
serve-status-edit-set workflow stops failing. Only the services-oriented
content is applied; any node-level fields are skipped with a warning to
stderr pointing users at get-config to migrate.
Fixestailscale/corp#39793
Signed-off-by: Brendan Creane <bcreane@gmail.com>