feat(train): a ride's distance from the wheel where GPS falls short (ADR 0030, D49)

The speed sensor's wheel gives a ride's distance, splits, progress and live
speed where GPS made less than 90 % of its way (a turbo trainer, a tunnel);
its circumference starts at 2105 mm, is learnt from rides with 2 km of GPS
or typed on the Record sheet.

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

@@ -34,6 +34,7 @@ class FakeRecorderPlatform({
           Map<String, Object?>? announce,
           String? speedSensor,
           String? powerMeter,
+          int? wheelMm,
         })
       >[];
 
@@ -95,6 +96,7 @@ class FakeRecorderPlatform({
     Map<String, Object?>? announce,
     String? speedSensor,
     String? powerMeter,
+    int? wheelMm,
   }) async {
     started.add((
       path: path,
@@ -109,6 +111,7 @@ class FakeRecorderPlatform({
       announce: announce,
       speedSensor: speedSensor,
       powerMeter: powerMeter,
+      wheelMm: wheelMm,
     ));
     notices.add(notice);
     _file = File(path)