Adds <summary>/<param>/<returns>/<inheritdoc> where missing and removes
project bookkeeping IDs (task/tracking refs) from shipped code comments,
so the docs read cleanly and CommentChecker is quiet except for known
false positives (PLC/protocol terms, event/IEqualityComparer inheritdoc).
Doc/comment-only; no logic changed; solution builds clean.
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.