Phase 4: history view with reverse geocoding

3-section layout (15/70/15) for browsing recorded events.
Reverse-geocodes coordinates via Photon API with Haversine
distance check and address caching. Also adds simulator GPS
polling fallback (Position.getInfo) since the simulator does
not fire location event callbacks.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

source/GeocodingService.mc

@@ -0,0 +1,83 @@
+import Toybox.Communications;
+import Toybox.Lang;
+
+// Reverse-geocodes a lat/lon pair via Photon API. Calls back with
+// a formatted address string or null on failure.
+class GeocodingService {
+
+    private var _callback as Method(address as String or Null) as Void;
+    private var _lat as Float;
+    private var _lon as Float;
+
+    function initialize(lat as Float, lon as Float,
+                        callback as Method(address as String or Null) as Void) {
+        _callback = callback;
+        _lat = lat;
+        _lon = lon;
+    }
+
+    function start() as Void {
+        var url = Config.PHOTON_URL;
+        var params = { "lon" => _lon, "lat" => _lat, "limit" => 1 };
+        var options = {
+            :method => Communications.HTTP_REQUEST_METHOD_GET,
+            :responseType => Communications.HTTP_RESPONSE_CONTENT_TYPE_JSON,
+            :headers => { "Accept" => "application/json" }
+        };
+        Communications.makeWebRequest(url, params, options, method(:_onResponse));
+    }
+
+    function _onResponse(responseCode as Number, data as Dictionary or String or Null) as Void {
+        if (responseCode != 200 || data == null || !(data instanceof Dictionary)) {
+            _callback.invoke(null);
+            return;
+        }
+
+        var features = data["features"];
+        if (features == null || !(features instanceof Array) || features.size() == 0) {
+            _callback.invoke(null);
+            return;
+        }
+
+        var feature = features[0] as Dictionary;
+        var props = feature["properties"] as Dictionary;
+        var geometry = feature["geometry"] as Dictionary;
+
+        // Haversine check: only use address if result is within threshold.
+        if (geometry != null) {
+            var coords = geometry["coordinates"] as Array;
+            if (coords != null && coords.size() >= 2) {
+                var rLon = (coords[0] as Double).toFloat();
+                var rLat = (coords[1] as Double).toFloat();
+                var dist = Haversine.distance(_lat, _lon, rLat, rLon);
+                if (dist > Config.ADDRESS_MAX_DISTANCE_M) {
+                    _callback.invoke(null);
+                    return;
+                }
+            }
+        }
+
+        _callback.invoke(_formatAddress(props));
+    }
+
+    private function _formatAddress(props as Dictionary) as String {
+        var street = props["street"];
+        var number = props["housenumber"];
+        var city = props["city"];
+
+        var parts = "";
+        if (street != null) {
+            parts = street as String;
+            if (number != null) {
+                parts = parts + " " + number;
+            }
+        }
+        if (city != null) {
+            if (!parts.equals("")) {
+                parts = parts + ", ";
+            }
+            parts = parts + city;
+        }
+        return parts.equals("") ? "Unbekannt" : parts;
+    }
+}