[codex] Surface weather live fail-closed health

[ijlu]

Summary

• Add live_fc_missing_skips to the existing [health] wx_handler daemon log line.
• Add a [health] wx_live_fail_closed line for live v2 fair-value fail-closed events.
• Escalate the v2 fail-closed health line to WARNING when nonzero, then reset the counter after each health emit.

Why

Batch 3 made live weather quoting fail closed when required forecast/v2 inputs are unavailable. This follow-up makes those fail-closed paths visible in daemon health logs so operators can distinguish safe skipping from quiet inactivity.

Validation

• python3 -m pytest tests/daemon/test_weather_live_health.py -q: 2 passed
• python3 -m pytest tests/daemon/test_weather_live_health.py tests/daemon/test_weather_handler.py tests/test_weather_quoter.py tests/test_snapshot_writer_health.py -q: 138 passed
• .venv/bin/python -m pytest tests/ -q: 2376 passed

Note: python3 -m pytest tests/ -q with the system Python failed during collection because the local system cryptography/_cffi_backend wheel is x86_64 while this machine needs arm64. The repo .venv full suite passed.

Notes

Stacked on codex/weather-live-fail-closed. No deploy or production data touched.