feat(train): workouts' weather from Open-Meteo, through the instance (ADR 0036)

A workout with a track gets the weather over it as its page opens, once
while it has none: the hours from the one it started in to the one it
ended in, kept in its sealed payload (temperature, feels-like, humidity,
precipitation, the WMO code, the wind, its gusts and direction) and shown
under its totals with the link to Open-Meteo its licence asks for.

Train's server asks Open-Meteo in the person's place (the `weather`
endpoint), so Open-Meteo never sees their address: the place rounded to
two decimals (also on the phone), a span of at most 48 hours, the
forecast API for recent spans and the archive for older ones, for people
signed in, at most 30 requests a person a minute, nothing kept or
logged. On by default; `WEATHER=off` switches it off, and
`OPEN_METEO_API_KEY` moves it to the paid hosts for an instance used
commercially.

Health Connect's fingerprint leaves the weather out, so keeping it
writes nothing again. No table and no migration.

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_server/test/integration/test_tools/serverpod_test_tools.dart

@@ -28,6 +28,8 @@ import 'package:halkyon_train_server/src/generated/routing/route_profile.dart'
     as _iex9meso;
 import 'package:halkyon_train_server/src/generated/search/place.dart'
     as _i6fosizj;
+import 'package:halkyon_train_server/src/generated/weather/weather_hour.dart'
+    as _io7n438g;
 import 'package:serverpod/serverpod.dart' as _is;
 import 'package:serverpod_test/serverpod_test.dart' as _ist;
 import 'package:halkyon_train_server/src/generated/protocol.dart';
@@ -172,6 +174,8 @@ class TestEndpoints {
   late final _RoutingEndpoint routing;
 
   late final _SearchEndpoint search;
+
+  late final _WeatherEndpoint weather;
 }
 
 class _InternalTestEndpoints extends TestEndpoints
@@ -197,6 +201,10 @@ class _InternalTestEndpoints extends TestEndpoints
       endpoints,
       serializationManager,
     );
+    weather = _WeatherEndpoint(
+      endpoints,
+      serializationManager,
+    );
   }
 }
 
@@ -506,6 +514,84 @@ class _SearchEndpoint {
   }
 }
 
+class _WeatherEndpoint {
+  _WeatherEndpoint(
+    this._endpointDispatch,
+    this._serializationManager,
+  );
+
+  final _is.EndpointDispatch _endpointDispatch;
+
+  final _is.SerializationManager _serializationManager;
+
+  _ida.Future<bool> offered(_ist.TestSessionBuilder sessionBuilder) async {
+    return _ist.callAwaitableFunctionAndHandleExceptions(() async {
+      var _localUniqueSession =
+          (sessionBuilder as _ist.InternalTestSessionBuilder).internalBuild(
+            endpoint: 'weather',
+            method: 'offered',
+          );
+      try {
+        var _localCallContext = await _endpointDispatch.getMethodCallContext(
+          createSessionCallback: (_) => _localUniqueSession,
+          endpointPath: 'weather',
+          methodName: 'offered',
+          parameters: _ist.testObjectToJson({}),
+          serializationManager: _serializationManager,
+        );
+        var _localReturnValue =
+            await (_localCallContext.method.call(
+                  _localUniqueSession,
+                  _localCallContext.arguments,
+                )
+                as _ida.Future<bool>);
+        return _localReturnValue;
+      } finally {
+        await _localUniqueSession.close();
+      }
+    });
+  }
+
+  _ida.Future<List<_io7n438g.WeatherHour>> hours(
+    _ist.TestSessionBuilder sessionBuilder, {
+    required double lat,
+    required double lon,
+    required DateTime from,
+    required DateTime to,
+  }) async {
+    return _ist.callAwaitableFunctionAndHandleExceptions(() async {
+      var _localUniqueSession =
+          (sessionBuilder as _ist.InternalTestSessionBuilder).internalBuild(
+            endpoint: 'weather',
+            method: 'hours',
+          );
+      try {
+        var _localCallContext = await _endpointDispatch.getMethodCallContext(
+          createSessionCallback: (_) => _localUniqueSession,
+          endpointPath: 'weather',
+          methodName: 'hours',
+          parameters: _ist.testObjectToJson({
+            'lat': lat,
+            'lon': lon,
+            'from': from,
+            'to': to,
+          }),
+          serializationManager: _serializationManager,
+        );
+        var _localReturnValue =
+            await (_localCallContext.method.call(
+                  _localUniqueSession,
+                  _localCallContext.arguments,
+                )
+                as _ida.Future<List<_io7n438g.WeatherHour>>);
+        return _localReturnValue;
+      } finally {
+        await _localUniqueSession.close();
+      }
+    });
+  }
+}
+
 class _PruningFutureCall {
   Future<void> pruneAccounts(_ist.TestSessionBuilder sessionBuilder) async {
     var _localUniqueSession =