Adds spans to 15 previously-unmeasured hot paths so every question we
might ask while tuning has a histogram to answer it:
External I/O:
- iem.fetch_iemre (gridded weather reanalysis)
- mrms.list_latest / mrms.download (precip radar)
- rtma.fetch_observation
- ncei.fetch_metar (historical 5-min METAR backfill)
- solar.fetch_indices (GFZ solar indices)
- swpc.fetch (SWPC Kp/F10.7/X-ray)
- giro.fetch (ionosonde)
- qrz.request, geocoder.geocode (callsign enrichment)
- srtm.download_tile (terrain tile download + gunzip)
- hrrr.download_grib_ranges (parallel byte-range fetch phase)
Subprocess:
- wgrib2.extract_grid / extract_grid_from_file / extract_grid_from_file_mapped
LiveView hot paths:
- propagation.scores_at (map score fetch + cache hit/miss counter)
- propagation.point_forecast (sparkline)
- propagation.point_detail (click-to-inspect)
- propagation.daily_outlook_at (/map outlook strip)
Worker-level end-to-end:
- worker.terrain_profile
- worker.mechanism_classify
- worker.mrms_fetch
Each event is registered in Microwaveprop.PromEx.InstrumentPlugin as
a Prometheus histogram (default / long buckets as appropriate) plus
a counter for the scores_at cache hit/miss ratio. Prometheus at
10.0.15.25 will start seeing the new series on the next scrape after
deploy.
RtmaClient was the only weather client without a Req.Test plug seam —
added the standard req_options() helper matching NarrClient/HrrrClient/
etc. so its HTTP calls can be stubbed in test.
17 characterization tests: URL construction, idx fetch 404/503, hour
truncation, malformed idx, range-GET error propagation, worker's
existing-row short-circuit, client-error propagation. GRIB2 byte
parsing paths deferred to the wgrib2 coverage task.
