Test plan: Native Policy Editor & Collaborative Authoring

• Edit an existing published KB article; confirm a new draft version is checked out on first edit rather than mutating the published version in place.
• Create a brand-new policy from within the editor (not from an existing article) and assign a manager to it; confirm both the new KB article and the manager assignment persist correctly.
• Open the same draft with two HR Policy Owner sessions simultaneously; type in both at once and confirm neither edit is silently dropped or overwritten (CRDT merge behaves correctly under concurrent typing, including near-simultaneous edits to the same line).
• Publish a draft; confirm the KB version increments, the prior version remains listable, and the advisor's retrieval index reflects the new content on the very next query (not stale from cache).
• Kill one collaborator's session mid-edit (e.g. close the tab); confirm the remaining collaborator's session is unaffected and can still publish.
• Confirm the WebSocket collaborative-edit relay's dependency on the Nova Advisor Agent doesn't silently disable co-editing if the advisor agent is down — either co-editing degrades gracefully (e.g. single-editor mode) or the failure is surfaced clearly to the user, not a silent hang.
• Attempt to publish as a role without Policy Owner permissions; confirm it's blocked.