[Subtask] Let EntityStore callers request a fresh read #13629

Describe the subtask

Priority: P2 (C8)

Problem: Reads may come from the per-node entity cache, which the change log invalidates only eventually, and the interface neither says so nor lets a caller ask for the stored state. Decisions such as observing an entity before an external call (#13172), in-use checks and ownership checks can act on a stale value.

Scope: Document when a read may be stale, add a way to request a read that bypasses the cache, and list the paths that must use it.

Parent issue

#13621