Wrap an already-materialized snapshot. Trusts `registry` to match `history`; advances the clock past every observed timestamp but does not re-apply ops. `history` is taken in on-disk (topological) order.
(peer: PeerId, registry: Registry, history: Vec<Delta>, head: Option<Rev>, redo_stack: Vec<Rev>, next_node_counter: u64)
source not stored for this graph (policy: none)