Neo X Reth 2.4.4

neox-v2.4.4

Code review fixes across three Neo X surfaces. Nothing consensus-visible: no
block this client produces or accepts changes, and the on-disk DKG keystore
format is unchanged.

• Keystore scrypt no longer blocks the async worker hosting the DKG runtime,
  and a completed keystore write no longer reports failure when a concurrent
  deleter removes its temporary file.
• Inbound dBFT messages are hashed once rather than twice, and both seal
  schemes now derive from one reconstructed unsigned header so they cannot
  drift on which bytes a seal commits to.
• Beacon streams declined at the admitted-peer ceiling are logged; the ceiling
  is fixed at 128 peers and does not widen with the node's peer limit.

Same pinned Reth baseline as neox-v2.4.1. Validator mode remains experimental.