Fix editor Save As confirmation, prevent opening empty filename

The confirmation popup was not shown for the Save As dialog anymore, due to the label being changed to `Save As` for the respective quick action. This check based on string comparison is rather brittle and can be replaced with comparison of the storage type with `IStorage::TYPE_SAVE`.

When the file dialog is used to open files, prevent opening files with an empty filename if enter is pressed while no file is selected (i.e. when the filter excludes all entries).

src/game/editor/editor.cpp

@@ -5353,20 +5353,25 @@ void CEditor::RenderFileDialog()
 			str_format(m_aFileSaveName, sizeof(m_aFileSaveName), "%s/%s", m_pFileDialogPath, m_FileDialogFileNameInput.GetString());
 			if(!str_endswith(m_aFileSaveName, FILETYPE_EXTENSIONS[m_FileDialogFileType]))
 				str_append(m_aFileSaveName, FILETYPE_EXTENSIONS[m_FileDialogFileType]);
-			if(!str_comp(m_pFileDialogButtonText, "Save") && Storage()->FileExists(m_aFileSaveName, StorageType))
+			const bool SaveAction = m_FileDialogStorageType == IStorage::TYPE_SAVE;
+			if(SaveAction && Storage()->FileExists(m_aFileSaveName, StorageType))
 			{
 				if(m_pfnFileDialogFunc == &CallbackSaveMap)
 					m_PopupEventType = POPEVENT_SAVE;
 				else if(m_pfnFileDialogFunc == &CallbackSaveCopyMap)
 					m_PopupEventType = POPEVENT_SAVE_COPY;
 				else if(m_pfnFileDialogFunc == &CallbackSaveImage)
 					m_PopupEventType = POPEVENT_SAVE_IMG;
-				else
+				else if(m_pfnFileDialogFunc == &CallbackSaveSound)
 					m_PopupEventType = POPEVENT_SAVE_SOUND;
+				else
+					dbg_assert(false, "m_pfnFileDialogFunc unhandled for saving");
 				m_PopupEventActivated = true;
 			}
-			else if(m_pfnFileDialogFunc)
+			else if(m_pfnFileDialogFunc && (SaveAction || m_FilesSelectedIndex >= 0))
+			{
 				m_pfnFileDialogFunc(m_aFileSaveName, StorageType, m_pFileDialogUser);
+			}
 		}
 	}