Refactor plots

[Peter9192]

This PR changes the way plots are constructed. A context manager is introduced that takes care of general sizing and styling of the plots. Indiviual plot elements like legend, axes, (grid)lines, et cetera can can access this context, but their API is limited to only the features that are relevant for them. This leads to a very sleek and modular design, e.g.:

    <ChartContainer>
      <Legend entries={data} />
      <Chart title="Thermodynamic diagram">
        <AxisBottom
          domain={() => [-45, 50]}
          tickValues={temperatureLines}
          tickFormat={d3.format(".0d")}
          label="Temperature [°C]"
        />
        <AxisLeft
          type="log"
          domain={() => [basep, topPressure]}
          tickValues={pressureLines}
          tickFormat={d3.format(".0d")}
          label="Pressure [hPa]"
        />
        <ClipPath />
        <For each={temperatureLines}>{(t) => SkewTGridLine(t)}</For>
        <For each={pressureLines}>{(p) => LogPGridLine(p)}</For>
        <For each={dryAdiabats}>{(d) => DryAdiabat(d)}</For>
        <For each={data()}>{(d) => Sounding(d)}</For>
      </Chart>
    </ChartContainer>

A big advantage of this is that (default) sizing and styling is now done in one place (the chartcontainer), and is consistent across all plot types.

[Peter9192]

Apparently it makes a difference whether you use prop destructuring. Using props.chilren rather than children seems to have fixed the issue.