Auto: focas-f1a — ODBST status flags as fixed-tree nodes

Closes #257

src/ZB.MOM.WW.OtOpcUa.Driver.FOCAS/IFocasClient.cs

@@ -48,8 +48,37 @@ public interface IFocasClient : IDisposable
     ///     responds with any valid status.
     /// </summary>
     Task<bool> ProbeAsync(CancellationToken cancellationToken);
+
+    /// <summary>
+    ///     Read the full <c>cnc_rdcncstat</c> ODBST struct (9 small-int status flags). The
+    ///     boolean <see cref="ProbeAsync"/> is preserved for cheap reachability checks; this
+    ///     method exposes the per-field detail used by the FOCAS driver's <c>Status/</c>
+    ///     fixed-tree nodes (see issue #257). Returns <c>null</c> if the wire client cannot
+    ///     supply the struct (e.g. transport/IPC variant where the contract has not been
+    ///     extended yet) — callers fall back to surfacing Bad on the per-field nodes.
+    /// </summary>
+    Task<FocasStatusInfo?> GetStatusAsync(CancellationToken cancellationToken)
+        => Task.FromResult<FocasStatusInfo?>(null);
 }
 
+/// <summary>
+///     Snapshot of the 9 fields returned by Fanuc's <c>cnc_rdcncstat</c> (ODBST). All fields
+///     are <c>short</c> per the FWLIB header — small enums whose meaning is documented in the
+///     Fanuc FOCAS reference (e.g. <c>emergency</c>: 0=released, 1=stop, 2=reset). Surfaced as
+///     <c>Int16</c> in the OPC UA address space rather than mapped enums so operators see
+///     exactly what the CNC reported.
+/// </summary>
+public sealed record FocasStatusInfo(
+    short Dummy,
+    short Tmmode,
+    short Aut,
+    short Run,
+    short Motion,
+    short Mstb,
+    short EmergencyStop,
+    short Alarm,
+    short Edit);
+
 /// <summary>Factory for <see cref="IFocasClient"/>s. One client per configured device.</summary>
 public interface IFocasClientFactory
 {