0.6.3 — 2026-10-01

Bug-fix release on Reef 0.9.3 / 0.6.2. Narrows restart-failure accounting so
unknown/contract-empty exits no longer exhaust max_retries into fail maint.

• RESTART_FAILURE treats only exit_code > 0 as failure (not != 0).
  Contract-empty / unknown exits often yield exit_code=-1. The previous
  exit_code != 0 check burned those as failures and exhausted console-login
  retries into fail maint after a clean logout. handle_contract_event and
  handle_child_exit now require exit_code > 0 for RESTART_FAILURE.

• zygctl start clears the sticky restart_count. A manual restart must
  not immediately re-enter maint on the next exit. The clear is in
  cmd_start via clear_restart_count, not inside start_service — clearing
  there broke failer crash-loop tests. Narrowed so the integration suite stays
  282/282.