feat: multi-column legend with tooltips [KFMT] [DHIS2-18242]

[BRaimbault]

Implements DHIS2-18242

Description

Redesigns the legend to use a consistent column layout across the main app, download mode, and plugin (0.85× zoom):

• Column system: the legend renders as a table with dedicated columns for the color swatch, name, start value, dash separator, end value, and count — giving all legend types a uniform, aligned structure.
• Compact number format: range values switch to compact notation (k, M, B) when any value is too long to fit its column, or whenever named ranges are present. Counts are always compact. Hovering a compacted value shows the full number in a portal tooltip.
• Ellipsis + tooltips: long legend item names and bubble map labels are truncated with …; hovering reveals the full text via a position: fixed portal tooltip that escapes table/SVG clipping.
• Single design: the same Legend / LegendItem components now drive the drawer, the download panel, and the plugin — range suppression, decimal inference, and compact mode all resolve at the Legend level so each consumer gets consistent output.
• "" instead of "Not set": in events and tracked entity popups an events data table.
• Bug fixes: donut double-count for shared colors, empty value display, and layer error display in the legend and layer card.
• Bug fixes: allow -0 entry in input type number.

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Quality checklist

Add N/A to items that are not applicable.

• Dashboard tested
• Cypress and/or Jest tests added/updated
• Docs added N/A
• d2-ci dependencies replaced N/A
• Tester approved (JHØ)

[dhis2-bot]

🚀 Deployed on https://pr-3657.maps.netlify.dhis2.org

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
2.9% Duplication on New Code

See analysis details on SonarQube Cloud