fix: emit export pickup times as clock readings without an offset

src/Service/TravelExportBuilder.php

@@ -144,8 +144,15 @@ class TravelExportBuilder
         // getPickups() is what buys stringToDateTimeFuzzy() for both zeit shapes and
         // adjustOvernightTimes(), which rolls an 02:15 listed after a 23:59 onto the next
         // calendar day. Resolved once per travel date, then shared by its hotel rows.
+        //
+        // Resolved in UTC: the times are BusPro's clock readings, and in Europe/Berlin a
+        // bare 02:45 on the spring-forward night would move to 03:45.
         $pickups = $this->buildPickups(
-            $this->travelParser->getPickups($node->filterXPath('.//zustiege/zustieg'), $dateFrom, true),
+            $this->travelParser->getPickups(
+                $node->filterXPath('.//zustiege/zustieg'),
+                new \DateTimeImmutable($dateFrom->format('Y-m-d'), new \DateTimeZone('UTC')),
+                true,
+            ),
             $pickupMasterData,
             $pickupsWithoutMasterData,
         );
@@ -234,8 +241,9 @@ class TravelExportBuilder
                 'street' => $details?->street,
                 'time' => $pickup->time?->format('H:i'),
                 // Emitted for time-only sources too: adjustOvernightTimes() has already
-                // worked out the real day, and a null here would throw that away.
-                'datetime' => $pickup->time?->format('c'),
+                // worked out the real day, and a null here would throw that away. A clock
+                // reading without an offset, like `time`.
+                'datetime' => $pickup->time?->format('Y-m-d\TH:i:s'),
             ];
         }