[FLAG-1145][FLAG-1110] Support legend in bar chart widgets + add legend primary forest loss widget

[SARodrigues]

Overview

This PR adds a new WidgetChartLegend component to display legends below a chart.
Although it's currently being imported in WidgetComposedChart, it is made to be very generic and to work in a widget's body. It could potentially be displayed below other chart types.

Although it is built focused on column support (with optional titles), it does have a vertical prop to display columns vertically. This support is due to the inability to display columns in the map/analysis, but could be used if added to other widgets that are half size.

Notes:

• This PR is primarily to add support for this type of legend as requested; I've added a legend quickly to the emissions widget just for demonstration of the multi-column & title support. There is no active task to add the legend to the widget, so I just quickly matched it to the designs.
  • I'll be ensuring that support is to be removed before this PR gets merged
• This PR does include implementation for display in the forest loss widget, FLAG-1110.

Screenshots

Testing

Where to find two widgets with examples in order to verify the new legend support and options:

• Gas emissions by dominant driver:
  • Dashboard:
    • Select "Brazil"
    • Click on the "Climate" tab
  • Map
    • Run analysis on "Brazil"
    • Select on "Climate"
    • Select the "Forest greenhouse gas emissions" layer
• Primary forest loss
  • Dashboard
    • Visit the "Summary" tab
  • Map
    • Run analysis on "Brazil"
    • Select "Forest change"
    • Activate the "Tree cover loss" layer

Tracking

• FLAG-1145 | Support legend in bar chart widgets
• FLAG-1110 | Add annotation for dotted line on primary forest loss widget

[willian-viana]