Update campaign step

New step config. Canonical outbound fields per action_type: connect→message (optional, ≤300 chars) or messages{slug:text}; message→body (required) or messages{slug:text}; comment→comment_text (required) or messages{slug:text}. For new LinkedIn campaign maps, use exact linkedin_provider_id (ACoAAA...) keys only; for email maps, use exact lead_email keys only. Omit from_address unless the user explicitly provided one; Zevari resolves the verified sender. POST DESTINATIONS (canonical): set config.post_refs = { "<target_key>": { "id": "<numeric_activity_id>" } } for like_post / react_to_post / comment, or { "*": { "id": "..." } } for a global post. For connect/message contextual references, use config.context_post_refs with the same shape. To allow most-recent dynamic resolution, set config.post_resolution = "dynamic". For threaded replies, also set config.comment_id. Submitting config.post_id / post_url / context_post_id / context_post_url as object maps is rejected with invalid_post_destination_shape — use post_refs instead. Use config.instruction for internal notes. config.note is REJECTED.