Why: A scratch session is a private general-agent chat; it must work for its
owner without the RDM provider and must not share documents or context with any
other conversation.
Evidence: agent-exec run fb04c4a9 (pi, success); go test ./internal/store ./internal/server ./internal/runmgr ./internal/app pass.
Impact: Owner work/read on scratch bypasses the domain provider; non-owners and
shared adapters get NotFound. Scratch runs skip project context, knowledge
retrieval, owner/project context entries, user/project memory, and cross-session
reads (both directions). Knowledge add/search 400, rdm.* and formal project
commands 403, settings writes 400, uploads skip indexing, and deleting the sole
conversation removes the scratch project.
Refs: Agent-System-Dev docs/superpowers/specs/2026-10-22-scratch-session-general-agent-design.md
Co-authored-by: Cursor <cursoragent@cursor.com>
