Inconsistent dark incident tables, chart outlines, and entity table corners #36423

Description

Several table and chart surfaces are inconsistent in the dark theme:

• Incident tables in the group drawer, drill-down, and entity incident tab use the lighter card surface instead of the darker table surface used by other listings. The entity incident filter band has the same mismatch.
• Donut charts draw a dark outline around each segment that contrasts with the surrounding card.
• Entity table containers have square corners while adjacent cards are rounded.

Expected behavior

Use the existing muted table surface for incident listings and their filter container, blend chart segment borders into the card background, and use the standard card corner radius for entity tables. Preserve light-theme appearance and existing table interactions.

Reproduction

1. Enable AI mode and the dark theme.
2. Open Incident Manager and preview an incident group.
3. Open a table's Data Observability > Incidents tab.
4. Inspect the data-quality summary donut charts and the entity's Columns table.