fix: WinDbg provider stops auto-selecting module, new tabs inherit source

- WinDbg provider no longer picks arbitrary module[0] as name/base
  (was showing "WS2_32" for kernel dumps). Name is now generic
  "WinDbg (Live)" / "WinDbg (Dump)", base stays 0 so controller
  doesn't override user's address.
- Added throttled read failure logging to WinDbg provider.
- New tabs (File→New Class, workspace right-click) inherit the
  current tab's source/provider so users don't have to re-attach.
- Updated WinDbg provider tests for new behavior.

src/main.cpp

@@ -1994,7 +1994,22 @@ QMdiSubWindow* MainWindow::project_new(const QString& classKeyword) {
 
     buildEmptyStruct(doc->tree, classKeyword);
 
+    // Inherit source from current tab (if any)
+    auto* currentCtrl = activeController();
+    if (currentCtrl && currentCtrl->document()->provider
+        && currentCtrl->document()->provider->isValid()) {
+        doc->provider = currentCtrl->document()->provider;
+    }
+
     auto* sub = createTab(doc);
+
+    // Copy saved sources to new tab's controller
+    if (currentCtrl && !currentCtrl->savedSources().isEmpty()) {
+        auto& newTab = m_tabs[sub];
+        newTab.ctrl->copySavedSources(currentCtrl->savedSources(),
+                                       currentCtrl->activeSourceIndex());
+    }
+
     rebuildWorkspaceModel();
     return sub;
 }