cyw43_spi_transfer calls pio_sm_restart before each transfer's count words, so
hooking restart() to reset the sniffer makes framing deterministic across the
firmware-stream fast-path (no phantom-transfer carryover). Verified: restarts
fire 3625x (once per transfer), F1 phantom count drops, and the CLM IOCTL write
now frames correctly (cmd decodes to F2, 'clmload' payload). Wired into
RP2040Simulator + the harness.
Remaining (next session): the CLM/IOCTL write doesn't complete its payload and
wifi_on still fails (active()=False) — bus_init stalls at/around clm_load with
only 2 STATUS reads and goes idle. Next: trace the CLM write's DMA/PIO drain and
the SDPCM IOCTL response path. See findings.md F-13.
b172cadbc5