Move FocasDriverOptions (and companion option types), FocasCncSeries,
and the FocasDataType enum to a new Driver.FOCAS.Contracts sibling
project. FocasDataTypeExtensions (which uses DriverDataType from
Core.Abstractions) stays in the runtime driver as FocasDataTypeExtensions.cs.
Convert two doc-comment references:
<see cref="FocasDriver.InitializeAsync"/> → <c>FocasDriver.InitializeAsync</c>
<see cref="FocasAddress.TryParse"/> → <c>FocasAddress.TryParse</c>
per the approved decision — no compilable usings were present in the
moved files.
The runtime Driver.FOCAS project gains a ProjectReference to .Contracts;
the .slnx is updated accordingly.