Renders a Chart.js line graph supporting up to two data series, with responsive canvas sizing and an optional Y-axis maximum.
EVENTLINE — set as ReportType in def_report.
def Render(self, Param1="", Param2="", Param3="") -> str:
The query must return rows with columns: label (col 0), series 1 value (col 1), series 2 value (col 2, optional). Series colours are resolved from $theme-primary$ and $theme-secondary$ configuration tokens. An optional _Maxval attribute caps the Y-axis.
Requires chart.min.js. The canvas is styled to fill 100% width at auto height.