Public snapshot state stays in the store engine's plain-data vocabulary
(immer drafts reject Sets without the MapSet plugin, which stays off):
manager/service/contract carry readonly SessionId[] in Host order, and
the tree derivations build their own transient Set — the
expandedProjects pattern. Membership-unchanged installs still keep the
array reference for Object.is short-circuits.
- WorkspaceRegistry.archiveSession no longer wraps persistence-listing
failures as WorkspaceUnknownSessionError: only a definite miss (live
lookup, header index, then a fresh list) maps to session-not-found;
storage faults propagate as internal errors, with a negative test.
- The archived-current sweep moves from the unary path into the
projection: any install path (local echo, another tab's frame, a
reconnect baseline) clears a selection that landed in the archive set.
- An archive set installed while workspace.list is in flight supersedes
the stale baseline's set instead of being rolled back by it.
- The workspace-management e2e anchors the archived row by its session
actions button and asserts the single-stray fixture assumption loudly.
- Drop the stale touchSession rows from the workspace READMEs (the
method was removed with its Agent Note).
