Continue Linux runtime foundation after #721. Add a dedicated credential worker with one outstanding request, bounded async wait, explicit cancellation/shutdown generations and stale-result suppression. Never launch unbounded blocking tasks or claim cancellation rolls back an in-flight store write. Fixed errors; bound request fields; test with fake stores, timeouts, cancellation, busy worker and recovery. Leave production runtime activation, pairing and input disabled. PR targets linux-support and depends on #721.
Continue Linux runtime foundation after #721. Add a dedicated credential worker with one outstanding request, bounded async wait, explicit cancellation/shutdown generations and stale-result suppression. Never launch unbounded blocking tasks or claim cancellation rolls back an in-flight store write. Fixed errors; bound request fields; test with fake stores, timeouts, cancellation, busy worker and recovery. Leave production runtime activation, pairing and input disabled. PR targets linux-support and depends on #721.