Fix #5480: narrow ActorOptions.snapshot and getPersistedSnapshot() to SnapshotFrom<TLogic>

[ther12k]

Closes #5480

Problem

ActorOptions.snapshot and Actor.getPersistedSnapshot() were typed
Snapshot<unknown> (a 4-shape union of status / output /
error). Real machine snapshots (MachineSnapshot<...>) have a
richer shape (status / value / context / matches(...) /
...). The two shapes do not overlap, so the round-trip
getPersistedSnapshot() → useMachine(machine, { snapshot })
failed typecheck even though the runtime is fine.

The deprecated state alias had the same problem.

Fix

Narrow both sides of the round-trip to SnapshotFrom<TLogic> so
the types agree:

• packages/core/src/types.ts — ActorOptions.snapshot and
  ActorOptions.state now use SnapshotFrom<TLogic> instead of
  Snapshot<unknown>.
• packages/core/src/createActor.ts —
  Actor.getPersistedSnapshot() return type is now
  SnapshotFrom<TLogic>. The internal
  this.logic.getPersistedSnapshot(...) call still returns
  Snapshot<unknown> per ActorLogic's generic declaration, so
  a single cast is applied at the public boundary. Runtime
  behaviour is unchanged.

For a StateMachine, SnapshotFrom<TMachine> resolves to
MachineSnapshot<...> via ReturnType<R['transition']>, which
is exactly what getPersistedSnapshot() returns at runtime.

Test

packages/xstate-react/test/types.test.tsx gets a new
it('useMachine accepts a rehydrated snapshot from getPersistedSnapshot #5480', ...) that exercises the round-trip
end-to-end and is expected to typecheck without as any or
@ts-expect-error. Two existing tests
(createActorContext.test.tsx, useActor.test.tsx) are updated
to use SnapshotFrom<typeof machine> for their persistedState
annotations to keep tsc green.

Verification

• pnpm typecheck → 0 errors (3 errors before the test-file
  annotations were updated; now clean).
• pnpm test:core is gated on Node ≥ 22 in this repo (uses
  Promise.withResolvers) — environment issue unrelated to this
  change.

Backward-compatible: callers passing a hand-written
Snapshot<unknown> to snapshot: are unaffected because the
internal _initState / restoreSnapshot flow still accepts any
shape that the logic's restoreSnapshot can convert.

[changeset-bot]

🦋 Changeset detected

Latest commit: ab963e3

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
xstate	Patch
@xstate/react	Patch

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