Big mixed day. Added a unified terrain search endpoint that hits ski areas, runs, and lifts in parallel, with PostGIS centroids as a fallback when an area is missing lat/lon, plus a web simulator and a bbox mode for the graph builder so I can rebuild a region without rebuilding the world. Loosened the background activity inference thresholds because the old ones were stubbornly classifying actual skiing as a "transition" at 18 km/h, and split tracking into a passive monitoring mode so auto-detect keeps working with the screen off. Also merged the responsive iPhone PR and wired up session file imports from AirDrop, which involved remembering that security-scoped resources exist. Two large markdown exploration reports landed in the repo root from the search planning pass, which I will probably move or delete later.

3 commits across 1 repo (schuss: 3). 68 files changed; 1 skipped. Diff was truncated for summarization.