Close the Otii switchboard relays during bench and verify

[byeongjee]

ckpt bench and ckpt verify run on continuous power, so they do not need the Otii. But when the intermittent-power rig is wired up, the ez-FET's SBW and 3V3 lines reach the target through the Qoitech switchboard relays, which an intermittent run leaves open. Both commands then find no device and silently degrade to compile-only. Closing the relays first lets them run without rewiring the board.

• _otii_device() holds the shared session setup and teardown, leaving the relays as the caller set them.
• otii_session() layers the relay-open on top, for intermittent runs; intermittent/runner.py is unchanged.
• debugger_connection() closes the relays and holds them closed. It is a no-op when no Otii is reachable (package, server, or device missing), so a directly wired board is unaffected.
• optional_saleae() (all five bench commands) and verify_algorithms() enter it before probing for the device.

Testing

On the rig, starting from the open-relay state an intermittent run leaves behind:

• mspdebug before/inside/after debugger_connection(): unreachable, then MSP430FR5994 detected, and still detected after the session shuts down — the relays hold their state once the client and server exit.
• ckpt bench milp crc --cap 1uF: flashed, timed (12118.86us), and read back NVM counters instead of degrading to compile-only.
• ckpt verify milp crc --cap 1uF: PASS (baseline=39423 milp=39423).
• The no-Otii path no-ops as intended.

A full ckpt intermittent run was not repeated; its only change is where the relay-open happens during teardown, which the runs above exercised.