This is easily solved using Scheduler Pro which has support for resource calendars, handling it automatically.
For regular Scheduler you have to solve this yourself, a bit more work... You can query your resourceTimeRangeStore in your https://bryntum.com/docs/scheduler/#Scheduler/feature/EventDrag#config-validatorFn
using https://bryntum.com/docs/scheduler/#Core/data/Store#function-query
to find ranges in the store that intersect with the current drag position.
See https://bryntum.com/examples/scheduler/validation/ also for more inspiration.