Add device-certificate mTLS auth, live position tracking, and API docs

Introduces a CA/PKI module so field devices can authenticate to Mosquitto
over TLS (8883) with per-device client certificates (CN = serial number)
instead of a shared password, with matching Devices/MQTT-Certs UI. Adds
live transmitter position tracking alongside logged points, an MQTTS
transport option in the simulator for exercising the real cert-auth path,
and Swagger API docs at /api/docs.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

web/components/map/google/GoogleJobMap.tsx

@@ -17,6 +17,13 @@ function orderKey(p: MapPoint): number {
   return p.sequence ?? new Date(p.recordedAt).getTime();
 }
 
+// Identifies whether the set of points (including each one's own position)
+// has actually changed, so a moving point re-fits bounds even when the
+// count doesn't change (e.g. a device's single "current location" point).
+function pointsSignature(points: MapPoint[]): string {
+  return points.map((p) => `${p.id}:${p.lat.toFixed(7)}:${p.lng.toFixed(7)}`).join('|');
+}
+
 // Draws points as colored circles plus one polyline per utility run.
 // Imperative overlays (google.maps.Marker/Polyline) are used because
 // @vis.gl/react-google-maps has no polyline component.
@@ -31,7 +38,7 @@ function PointsLayer({
 }) {
   const map = useMap();
   const overlaysRef = useRef<{ setMap: (m: google.maps.Map | null) => void }[]>([]);
-  const fittedCountRef = useRef(0);
+  const fittedSignatureRef = useRef('');
   const onSelectRef = useRef(onSelect);
   onSelectRef.current = onSelect;
 
@@ -85,11 +92,18 @@ function PointsLayer({
       }
     }
 
-    if (fitBounds && points.length !== fittedCountRef.current) {
-      fittedCountRef.current = points.length;
-      const bounds = new google.maps.LatLngBounds();
-      points.forEach((p) => bounds.extend({ lat: p.lat, lng: p.lng }));
-      map.fitBounds(bounds, 48);
+    const signature = pointsSignature(points);
+    if (fitBounds && signature !== fittedSignatureRef.current) {
+      fittedSignatureRef.current = signature;
+      if (points.length === 1) {
+        // A single (often moving) point has no useful bounds to fit — just
+        // recenter on it, preserving the current zoom.
+        map.panTo({ lat: points[0].lat, lng: points[0].lng });
+      } else {
+        const bounds = new google.maps.LatLngBounds();
+        points.forEach((p) => bounds.extend({ lat: p.lat, lng: p.lng }));
+        map.fitBounds(bounds, 48);
+      }
     }
   }, [map, points, fitBounds]);
 
@@ -157,6 +171,9 @@ function LiveMarker({ status, onSelect }: { status: LiveStatus | null; onSelect:
       haloRef.current?.setCenter(position);
       haloRef.current?.setRadius(status.hAccuracy ?? 5);
     }
+
+    // Follow the transmitter as its position updates.
+    map.panTo(position);
   }, [map, status]);
 
   useEffect(
@@ -211,14 +228,18 @@ export default function GoogleJobMap({ points, liveStatus = null, fitBounds = tr
   }
 
   // A point can be re-fetched (new object identity) between renders; keep the
-  // InfoWindow anchored to the latest copy of the same point by id. The live
-  // marker's "point" is synthesized fresh from liveStatus each time.
+  // InfoWindow anchored to the latest copy of the same point by id. The
+  // liveStatus marker's "point" is synthesized fresh from liveStatus each
+  // time — but only for the id it actually owns. Other callers (e.g. the
+  // devices page's single current-position point) may also use a "live-"
+  // prefixed id without ever passing a liveStatus prop, so that id alone
+  // can't be used to decide which source to read from.
   const selectedCurrent = (() => {
     if (!selected) {
       return null;
     }
-    if (selected.id.startsWith('live-')) {
-      return liveStatus ? liveStatusToMapPoint(liveStatus) : null;
+    if (liveStatus && selected.id === `live-${liveStatus.deviceId}`) {
+      return liveStatusToMapPoint(liveStatus);
     }
     return points.find((p) => p.id === selected.id) ?? selected;
   })();