- Add Apache echarts (https://echarts.apache.org/en/index.html) library to create build performance charts.
- Restructure data to time and value array format so that it can be used by echarts.
- This commit also converts test duration to minutes to map against the values axis.
- Zoom is added to the line charts.

…of commit number

- This commit updates measurement statistics data to include start_time so that time can be displayed instead of commit numbers on the chart.
- It also updates default commit history length to 300.

Styling updates are added including page margin, labels for x and y axis, tooltip, and section descriptions.

- Update chart tooltip format to show value as size in MB for 'rootfs size'
and timestamp for 'tmpdir size'
- Add commit number to tooltip
- Update chart type to 'step chart' instead of 'line chart'

Signed-off-by: Ninette Adhikari <[email protected]>

Update css to add dark mode when window prefers-color-scheme is dark.

Signed-off-by: Ninette Adhikari <[email protected]>