Forecast model processing preview 2 (Windows x64)

This is a Windows preview of the forecast-model integration for Supercell Wx. It is intended for testing and maintainer review, not as a replacement for the current stable release.

Download the ZIP, extract it to its own folder, and run bin\supercell-wx.exe. This is an unsigned portable build, so Windows may show a SmartScreen warning.

Review material

• Review branch
• Architecture and data-flow diagram
• User workflow and packaging notes

The architecture write-up covers the C++/Qt host boundary, optional helper process, versioned JSONL protocol, cache/store/artifact flow, cancellation and failure isolation, ProductDatastore alignment, and possible built-in or plugin-provider paths. Both documents are also included in the ZIP.

Preview 2 changes

• Find latest now confirms only the requested forecast hour instead of inventorying the model's complete forecast horizon. The same bounded path applies to every supported model; exact all-hour discovery remains an explicit helper operation.
• On the same HRRR/NOMADS request, latest-run discovery dropped from 125.8 seconds to 5.58 seconds. A GFS/NOMADS check completed in 0.57 seconds.
• Probe responses distinguish the confirmed hour from the model's cycle-aware supported-hour schedule while remaining compatible with the previous response format.
• The maintainer documentation now includes reviewer entry points and explicit comparisons for built-in C++, optional-helper, plugin-provider, and generalized-datastore approaches.

Included functionality

• A dedicated View > Forecast Models dock.
• Model, source, cycle, run, forecast-hour, and product discovery through the optional processor.
• Cached downloads with view, full, and sounding profiles. Heavy ECAPE processing remains a separate opt-in.
• Direct and derived products as georeferenced map overlays, with search, favorites, opacity, visibility, playback, and optional main-timeline synchronization.
• Point soundings using the full sharppyrs layout, including a responsive dock preview and resizable pop-out window.
• Progress and cancellation for downloads, map renders, and soundings.

Supercell Wx remains a C++/Qt application. Forecast processing runs in an optional child executable; no Rust ABI or Rust toolchain is added to the normal application build. If the helper is absent, the existing radar, alert, and map workflows continue normally.

Current limitations

• Model overlays are static rasters for the bounds selected when rendered. Moving outside those bounds requires another render, and images are capped at 4096 pixels per side.
• A point sounding requires an hour processed with the sounding profile. Cached source files can be reused when reprocessing an existing view-only hour.
• Soundings use the nearest usable model grid point and are forecast soundings, not observations.
• One model operation runs at a time. Heavy ECAPE processing can take considerably longer than the normal full profile.

Validation

• Windows x64 Release build completed at commit d6390a5326 without a dirty-worktree suffix.
• Two focused bridge probe tests and two Supercell Wx probe-contract tests passed.
• Live HRRR and GFS NOMADS probes returned the expected latest runs and cycle-aware schedules.