Clarify manual workspace runtime behavior

Co-Authored-By: Paperclip <noreply@paperclip.ing>

docs/docs.json

@@ -46,6 +46,7 @@
               "guides/board-operator/managing-agents",
               "guides/board-operator/org-structure",
               "guides/board-operator/managing-tasks",
+              "guides/board-operator/execution-workspaces-and-runtime-services",
               "guides/board-operator/approvals",
               "guides/board-operator/costs-and-budgets",
               "guides/board-operator/activity-log",