core: move workspace ptrs to weak (#11194)

Fixes some race conditions that come up in tests. We only clean up workspaces when we render a frame. With this, they are always cleared instantly.

src/desktop/Workspace.cpp

@@ -13,6 +13,7 @@ using namespace Hyprutils::String;
 PHLWORKSPACE CWorkspace::create(WORKSPACEID id, PHLMONITOR monitor, std::string name, bool special, bool isEmpty) {
     PHLWORKSPACE workspace = makeShared<CWorkspace>(id, monitor, name, special, isEmpty);
     workspace->init(workspace);
+    g_pCompositor->registerWorkspace(workspace);
     return workspace;
 }