Show 1990 emission values in emissions chart

[kndehaan]

Context

The various emissions charts show the emissions for 1990, start and future year. When opening table view only the values for start and future year are shown. See screenshots below.

Current shortcoming

It's desired to also have the 1990 emission values available in table view.

Proposed enhancement

Make the 1990 emission values available in table view. This should be about 0.5 day work. Some extra consideration needs to go to how the 1990 emissions would be visible in the CO2 emissions chart, where there are only three series for 1990 emissions instead of per sector division.

Success criteria

Users can directly compare 1990 emissions values with start and future year in the table overview of the emissions charts.

[kndehaan]

I had AI do I first attempt for this, created a draft PR here #4755. @louispt1 could you have a look at the code to see if it makes sense and if it's setup how we would do it, or whether it's at least on the right track? If changes are required, could you indicate how "intensive" the required changes are?

Besides the dev implementation, there's some deciding to do on the labelling and layout of table view as it should work nicely for all charts, also see screenshots below. Requires relabelling, adding 1990 target line in CO2 emissions chart, etc. Notifying @mabijkerk.