Frontend: Code Generation Volume Trends

Proposal

Let's add the Code Generation Volume Trends panel from https://gitlab.com/gitlab-org/gitlab/-/issues/570320#feature-level-analysis using a multi-series area chart visualization.

Data is already available in graphql: aiMetrics.codeSuggestions.shownLinesOfCode and aiMetrics.codeSuggestions.acceptedLinesOfCode filterable by month.

If the multi-series area chart is a blocker, go with whichever is quickest to implement and create a follow-up for the conversion to multi-series area chart

Implementation

• Create data source
• Add visualization template to GitLab Duo and SDLC trends dashboard