Merge pull request #21427 from tritao/async-occt-progress

Part: Introduce `OCCTProgressIndicator` and port operations to support it.

src/App/Application.h

@@ -36,6 +36,7 @@
 
 #include <Base/Observer.h>
 #include <Base/Parameter.h>
+#include <Base/ProgressIndicator.h>
 
 // forward declarations
 using PyObject = struct _object;
@@ -475,6 +476,9 @@ public:
     bool hasLinksTo(const DocumentObject *obj) const;
     //@}
 
+    /// Gets the base progress indicator instance.
+    Base::ProgressIndicator& getProgressIndicator() { return _progressIndicator; }
+
     friend class App::Document;
 
 protected:
@@ -662,6 +666,8 @@ private:
     int _activeTransactionGuard{0};
     bool _activeTransactionTmpName{false};
 
+    Base::ProgressIndicator _progressIndicator;
+
     static Base::ConsoleObserverStd  *_pConsoleObserverStd;
     static Base::ConsoleObserverFile *_pConsoleObserverFile;
 };