# Contract: Timeline Cards + Drilldown

## Card Grouping

- Render timeline as grouped cards (typically by day), not raw event rows.
- Correlated or visually equivalent events may be collapsed into one card with counts.
- Card summaries should be human-readable and avoid repeating page-scope identity labels.

## Filters

- Timeline filters are server-side when timeline is paginated or large.
- Filters should preserve grouping semantics and timezone behavior.
- Scope-invariant filters may be hidden on entity detail pages.

## Drilldown

- One card opens one drilldown modal/panel.
- Drilldown contains:
  - event list (left/top)
  - selected event details (right/bottom)
- No nested modal inside drilldown.
- Card-local search/filter may be applied within the drilldown.

## UX Rules

- Use human-readable source labels.
- Prefer action-oriented card titles (`Installed N components`, `Removed N components`).
- Empty states must explain whether filters removed all results.