Renders a horizontal grid of sub-reports, dividing the available width equally among the reports listed in the query.
GRID — set as ReportType in def_report.
def Render(self, Param1="", Param2="", Param3="") -> str:
Each query row supplies a sub-report name in col 0. Each sub-report is called with Param1 and proportional width/height derived from self._Width and self._Height. The report title (self._Title) is displayed centred below the grid.