Various ui enhancements
Aggregates the time to production and metrics summary by averaging by
date across all projects to get the value. Creates a single dataset for
the aggregation. This makes theme behave like eg the Health chart
(showing aggregated graph when show all projects and per project when
not)
Gradient fill when all projects across all related charts
Attached recording with generated data for 3 months
https://github.com/Unleash/unleash/assets/104830839/7acd80a8-b799-4a35-9a2e-bf3798f56d32
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Signed-off-by: andreas-unleash <andreas@getunleash.ai>