feat(train): a ride reads the bike's speed and cadence sensor and power meter (ADR 0030, D49)

11d, its sensors: a ride's Record sheet offers the CSC sensor (0x1816)
and the power meter (0x1818), found nearby and remembered as the strap
is; the person's devices are now one map of DeviceKind to DeviceStore.
The service parses CSC and Cycling Power measurements (JVM-tested,
counters' rollover, coasting), writes the wheel's revolutions, the
crank's cadence and the watts to the file and to series of their own.
The recording screen shows cadence and watts; the page the power's
chart, average, highest and normalised power and the cadence's chart and
average; GPX, TCX and FIT carry them. A plan's watts target reads the
power meter too.

The wheel's speed and distance follow. Not tried with a real sensor.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

apps/train/halkyon_train_flutter/test/support/fake_recorder_platform.dart

@@ -32,6 +32,8 @@ class FakeRecorderPlatform({
           Map<String, Object?>? route,
           Map<String, Object?>? music,
           Map<String, Object?>? announce,
+          String? speedSensor,
+          String? powerMeter,
         })
       >[];
 
@@ -42,6 +44,9 @@ class FakeRecorderPlatform({
   /// whether Bluetooth is on.
   List<FoundDevice> nearby = [];
   List<FoundDevice> nearbyRowers = [];
+
+  /// The bike's sensors nearby (D49).
+  List<FoundDevice> nearbyBike = [];
   bool bluetoothOn = true;
 
   /// The scans started, of which kind.
@@ -88,6 +93,8 @@ class FakeRecorderPlatform({
     Map<String, Object?>? route,
     Map<String, Object?>? music,
     Map<String, Object?>? announce,
+    String? speedSensor,
+    String? powerMeter,
   }) async {
     started.add((
       path: path,
@@ -100,6 +107,8 @@ class FakeRecorderPlatform({
       route: route,
       music: music,
       announce: announce,
+      speedSensor: speedSensor,
+      powerMeter: powerMeter,
     ));
     notices.add(notice);
     _file = File(path)
@@ -163,7 +172,11 @@ class FakeRecorderPlatform({
     if (!bluetoothOn) {
       return Stream.error(BluetoothOff());
     }
-    final found = kind == DeviceKind.strap ? nearby : nearbyRowers;
+    final found = switch (kind) {
+      DeviceKind.strap => nearby,
+      DeviceKind.rower => nearbyRowers,
+      DeviceKind.speedSensor || DeviceKind.powerMeter => nearbyBike,
+    };
     // Open until cancelled, as a scan is.
     return Stream.multi((listener) => found.forEach(listener.add));
   }