Load the single MEMORY document for a USER or WORKSPACE scope (full markdown_body).

Use when: Use before maintaining memory: retrieve the existing scoped memory document to merge an observation into it.

Behavior: read_only

workspace_id / user_id are injected from request headers.

Also returns pagination info (id, slug, family, scope, workspace_id, user_id, display_name, description, injection_strategy, priority, enabled, publish_status, tags, tool_binding_key, activation_conditions_json, visibility_conditions_json, metadata_json, published_version, created_at, updated_at, created_by, updated_by, latest_version, session_id, entity_type, entity_id).