Add Verpflegungsmehraufwand (VMA) as fixed facility condition field

Adds MealAllowanceRate as a flat, nullable EUR amount on Facility, following
the same pattern as the existing TravelCostRate/BillingRate fields — a fixed
per-facility rate, not the statutory day-based VMA tiers, per explicit
request.

Both generated API clients are regenerated/rebuilt as required after any
Contract/Controller change (see omsorgCore/CLAUDE.md, "Generierte API-
Clients"). The PHP client regen also picks up the DELETE /api/roles/{id}
endpoint added in a previous backend change but never synced to this client
until now.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

omsorgWeb/mitarbeiter-app/api-client-php/.openapi-generator/FILES

@@ -231,13 +231,3 @@ lib/Model/ValueListTransitionResponse.php
 lib/Model/ValueListUsageResponse.php
 lib/ObjectSerializer.php
 phpunit.xml.dist
-test/Api/EmployeeFacilityDistancesApiTest.php
-test/Api/MyFacilityDistancesApiTest.php
-test/Model/CreateEmployeeFacilityDistanceRequestTest.php
-test/Model/CreateMyFacilityDistanceRequestTest.php
-test/Model/EmployeeFacilityDistanceResponseTest.php
-test/Model/FacilityOptionResponseTest.php
-test/Model/MyFacilityDistanceResponseTest.php
-test/Model/TrashEmployeeFacilityDistanceResponseTest.php
-test/Model/UpdateEmployeeFacilityDistanceRequestTest.php
-test/Model/UpdateMyFacilityDistanceRequestTest.php