feat(draft): catch split text settings and owner-editable game ports

Two problems a draft can boot fine with but break once an owner changes a
setting, both in the builder's Valheim draft:

- splitSettings: text settings used unquoted on the command line, directly
  or through ARGS="-name ${SERVER_NAME}"; ./server $ARGS, so "GBRHosting -
  My Server" reaches the game as several arguments. Suggests quoting or a
  bash array.
- portSettings: game-port settings whose default isn't in defaultPorts, or
  that owners can change although nodes always publish the same container
  port. Internal ports (RCON, REST) and {PUBLIC_PORT_n} values are left out.

Both run on drafts only; AUTHORING.md gets the matching rules.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

cmd/gbrgames/draft.go

@@ -198,6 +198,8 @@ func (d *drafter) check(answer string) []string {
 			problems = append(problems, draftCompleteness(g, t)...)
 			problems = append(problems, unreadSettings(g, d.facts)...)
 			problems = append(problems, savesOutsideVolumes(g, d.job.Report)...)
+			problems = append(problems, splitSettings(g)...)
+			problems = append(problems, portSettings(g)...)
 		}
 	}
 	return problems