feat(commons): add IDriverBrowser/IBrowseSession/BrowseNode abstractions

src/Core/ZB.MOM.WW.OtOpcUa.Commons/Browsing/IBrowseSession.cs

@@ -0,0 +1,29 @@
+namespace ZB.MOM.WW.OtOpcUa.Commons.Browsing;
+
+/// <summary>
+///     A live, one-level-at-a-time browse over a remote address space. Owned by the
+///     AdminUI <c>BrowseSessionRegistry</c>; disposed by the registry's TTL reaper or
+///     the picker body on close.
+/// </summary>
+public interface IBrowseSession : IAsyncDisposable
+{
+    /// <summary>Opaque token identifying this session in the registry.</summary>
+    Guid Token { get; }
+
+    /// <summary>Wall-clock time of the most recent successful call. Refreshed on
+    /// <see cref="RootAsync"/>, <see cref="ExpandAsync"/>, and
+    /// <see cref="AttributesAsync"/>; used by the reaper for idle eviction.</summary>
+    DateTime LastUsedUtc { get; }
+
+    /// <summary>Returns the top-level browse nodes.</summary>
+    Task<IReadOnlyList<BrowseNode>> RootAsync(CancellationToken cancellationToken);
+
+    /// <summary>Returns the direct children of the node identified by
+    /// <paramref name="nodeId"/>.</summary>
+    Task<IReadOnlyList<BrowseNode>> ExpandAsync(string nodeId, CancellationToken cancellationToken);
+
+    /// <summary>Returns the attributes of the node identified by <paramref name="nodeId"/>.
+    /// Empty for drivers whose tree is uniform (OPC UA Client). Galaxy uses this to populate
+    /// the attribute side-panel after the user selects an object.</summary>
+    Task<IReadOnlyList<AttributeInfo>> AttributesAsync(string nodeId, CancellationToken cancellationToken);
+}