[History] 2 - Trim range selection

[KacperKozak]

Parent

• [PRD][History] Favorites #286

What to build

Trim range selection when creating a Favorite. The star action on an open history ride enters trim mode: two drag handles on the metric chart timeline (time is domain truth; map trimming is ambiguous on loops), defaulting to the full Moving Window. Dragging updates a live highlight of the selected sub-range on the map route and live-recomputed stats for the range. Save creates the Favorite from the selected range (free milliseconds — no snapping, no minimum range). Multiple Favorites can be created from one ride.

Likely files

• src/modules/history/components/HistorySessionSheet.tsx - hosts the star action and chart; trim mode lives here
• src/modules/history/components/historyChartMetrics.ts - chart data shaping for the timeline
• src/modules/history/lib/rideFormat.ts - stat formatting for the live recompute readout
• src/modules/history/store/historyStore.ts - selected session samples feeding live stats
• src/components/gestures/ - existing gesture primitives for drag handles

Implementation hints

• Live stats can be computed JS-side from already-loaded session samples for preview; the durable stats are still computed natively at creation (slice 1 API).
• Highlighting a sub-range on the route: filter loaded GPS samples by the handle range; reuse the existing route rendering path rather than a second map source if possible.
• Use Reanimated shared values for handle drags to avoid render storms (see docs/agents/react.md conventions).
• If the trim handles become a reusable control, add a showcase preview under src/app/settings/components/.

Acceptance criteria

• Star enters trim mode with handles defaulted to the full Moving Window
• Handles drag freely in time; no snapping, no enforced minimum
• Map highlights the selected sub-range live while dragging
• Stats readout recomputes live for the selected range
• Save creates a Favorite for exactly the selected range
• Creating several Favorites from the same ride works

Blocked by

• [History] 1 - Create and list Favorites #287

Related

• [History] 1 - Create and list Favorites #287
• [History] 3 - Pin favorited telemetry #289
• [History] 4 - Favorite detail and rename #290
• [History] 5 - Favorite media #291

[KacperKozak]

Resolved in PR #292.