feat: pin the fastest point on the trip replay map (FEAT-16)

When a route loads, add an amber circle + permanent 'Max speed: X km/h'
tooltip at the point with the highest speed. Shared history.js, so it
applies to both the Pi and the server portal.

FEATURES.md

@@ -35,6 +35,7 @@ dedicated PLAN.md phase (or fold it into the relevant existing work) and mark it
 | FEAT-13 | `IDEA` | Flush uploaded tracking rows from local DB | unassigned |
 | FEAT-14 | `SHIPPED` | Second T3U to replace onboard wlan0 (dual AC radios) | Phase 29 |
 | FEAT-15 | `SHIPPED` | Clear DTC codes from the DTC page | Phase 29 |
+| FEAT-16 | `SHIPPED` | Max-speed marker on trip replay map | Phase 29 |
 
 ---
 
@@ -291,3 +292,13 @@ dedicated PLAN.md phase (or fold it into the relevant existing work) and mark it
   `POST /api/dtc/clear` in `app.py`, and the button + confirm/status JS in `templates/dtc.html`.
 
 
+### FEAT-16 — Max-speed marker on trip replay map
+- **Status**: `SHIPPED` 2026-08-15
+- **Area**: `static/js/history.js`
+- **Phase**: Phase 29
+- **What**: when a trip's route loads, the replay map now pins the fastest point with an
+  amber circle + a permanent "Max speed: X km/h" tooltip. It uses the per-point speed (OBD
+  when available, otherwise the smoothed GPS-derived value), so it matches the trip summary's
+  `max_speed_kmh`. Works identically on the Pi and the server portal (shared `history.js`).
+
+

static/js/history.js

@@ -172,6 +172,24 @@
                 L.marker(coords[0]).bindPopup("Start").addTo(st.route);
                 L.marker(coords[coords.length - 1]).bindPopup("End").addTo(st.route);
             }
+            // Pin the fastest point on the route.
+            var maxPt = null;
+            for (var i = 0; i < d.points.length; i++) {
+                if (!maxPt || d.points[i].speed > maxPt.speed) maxPt = d.points[i];
+            }
+            if (maxPt && maxPt.speed > 0) {
+                L.circleMarker([maxPt.latitude, maxPt.longitude], {
+                    radius: 6,
+                    color: "#fff",
+                    weight: 2,
+                    fillColor: "#f6c23e",
+                    fillOpacity: 1,
+                })
+                .bindTooltip("Max speed: " + fS(maxPt.speed), {
+                    permanent: true, direction: "top", offset: [0, -8],
+                })
+                .addTo(st.route);
+            }
             st.route.addTo(map);
             if (sig.aborted) { cleanup(); return; }
             if (coords.length > 1) map.fitBounds(st.route.getBounds(), {padding: [24, 24], maxZoom: 15});