[gg582]

Summary

• add operator-only /ddial request, request-status, and request-cancel commands
• submit requests through a separate one-shot socket without changing or reconnecting the configured DDial relay
• persist the remote request id, station name, and hub address in ddial_outbound_request.dat with atomic writes and 0600 permissions
• support duplicate remote requests after local cancellation while explicitly leaving the remote pending request unchanged
• add eight-language help/messages and DDial documentation

Tests

• make -j2
• make unit-test
• make SANITIZE=address,undefined unit-test
• live loopback coverage for request submission, tracking reload, cancellation, same-id resubmission, operator checks, and relay-state isolation