nx_stream_picker.nx

nx_stream_picker.nx -- streaming + endgame piece selection (bits-up, deterministic). module: nishi-core.torrent.stream_picker depends: nx_piece_manager.nx (reuses nx_pm_rarest; DRY -- one canonical tie-break) capability: CORE_COMPUTE wired_status: FULLY_WIRED The modern "watch / play while you download" capability and the long-tail-killing endgame mode, with NO wall-clock and NO RNG -- every selection is bit-for-bit replayable (the determinism exceed thesis: no mainstream client can replay a swarm session). The player advertises a playhead (the piece it is about to render); the picker prioritizes a sliding deadline window so playback never starves, while still feeding rarest-first pieces to the swarm outside the window (swarm-health is not sacrificed for streaming -- BUILD intelligence, don't strip a feature). Endgame lets several peers race the final outstanding blocks (cancel the losers), killing the one slow peer who holds the last block -- the dominant source of completion-time variance. Pipeline depth is the request-queue throughput lever, derived from the bandwidth-delay product (no magic number: callers pass measured bandwidth/rtt and the ceiling config).