Add Explorer Workbench with hierarchical, off-UI Storage analysis.

Storage queries run in the background with cancellation and covering indexes so switching views no longer freezes the UI.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/Explorer.Domain/Enums.cs

@@ -0,0 +1,138 @@
+namespace Explorer.Domain;
+
+public enum SourceKind
+{
+    NtfsLocal,
+    Removable,
+    Smb,
+    Nfs,
+    Cloud
+}
+
+public enum SourceStatus
+{
+    Online,
+    Offline,
+    Scanning,
+    Stale,
+    Error
+}
+
+public enum EntryStatus
+{
+    Present = 0,
+    Offline = 1,
+    Deleted = 2,
+    Unknown = 3
+}
+
+public enum HashState
+{
+    None = 0,
+    Partial = 1,
+    Full = 2,
+    Skipped = 3
+}
+
+public enum CloudAvailability
+{
+    Unknown = 0,
+    OnlineOnly = 1,
+    LocallyAvailable = 2,
+    Pinned = 3,
+    Syncing = 4,
+    Error = 5
+}
+
+public enum ExcludeKind
+{
+    PathPrefix,
+    Glob,
+    Extension,
+    Attribute
+}
+
+public enum ScanKind
+{
+    Full,
+    Incremental,
+    Folder,
+    Rebuild
+}
+
+public enum ScanJobStatus
+{
+    Queued,
+    Running,
+    Cancelled,
+    Failed,
+    Done,
+    Interrupted
+}
+
+public enum TransferOp
+{
+    Copy,
+    Move,
+    Delete,
+    Rename,
+    NewFolder
+}
+
+public enum TransferStatus
+{
+    Queued,
+    Running,
+    Cancelling,
+    Cancelled,
+    Failed,
+    Done
+}
+
+public enum FolderViewMode
+{
+    Details,
+    List,
+    Preview
+}
+
+public enum SearchScopeKind
+{
+    CurrentFolder,
+    CurrentTree,
+    Selected,
+    Sources,
+    AllKnown,
+    OfflineMedia
+}
+
+public enum IndexFreshness
+{
+    Unknown,
+    Current,
+    Scanning,
+    Stale,
+    Offline,
+    NotIndexed
+}
+
+public static class AttributeFlags
+{
+    public const int ReadOnly = 1;
+    public const int Hidden = 2;
+    public const int System = 4;
+    public const int Directory = 16;
+    public const int Archive = 32;
+    public const int ReparsePoint = 1024;
+    public const int Offline = 0x1000;
+    public const int RecallOnOpen = 0x40000;
+    public const int Pinned = 0x80000;
+    public const int Unpinned = 0x100000;
+    public const int RecallOnDataAccess = 0x400000;
+
+    public static bool MayHydrateOnRead(int attributes)
+        => (attributes & (RecallOnDataAccess | Offline)) != 0;
+
+    public static bool IsPinned(int attributes)
+        => (attributes & Pinned) != 0 && (attributes & Unpinned) == 0;
+}