feat: Add span event annotations to waterfall view

[MikeShi42]

[changeset-bot]

🦋 Changeset detected

Latest commit: 28a4cb3

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@hyperdx/app	Minor
@hyperdx/api	Minor

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Review	Updated (UTC)
hyperdx-v2-oss-app	Ready	Preview, Comment	Dec 29, 2025 4:39pm

[claude]

Code Review

Critical Issues:

• ❌ Type mismatch in SpanEventMarkerComponent (TimelineChart.tsx:56) → marker.timestamp expects ms offset from minOffset but receives absolute timestamp. Should be formatTime(new Date(marker.timestamp + eventStart)) or change marker type comment.

Important:

• ⚠️ Potential rendering issue (TimelineChart.tsx:669) → marker.timestamp is calculated as absolute ms - minOffset, but SpanEventMarkerComponent uses it with formatTime as absolute timestamp. This will show wrong times in tooltips.

Suggested Fix:
In TimelineChart.tsx:56, change:

{formatTime(new Date(marker.timestamp), { format: 'withMs' })}

To:

{formatTime(new Date(eventStart + marker.timestamp), { format: 'withMs' })}

Otherwise the implementation looks solid - good job on the feature!

[github-actions]

E2E Test Results

✅ All tests passed • 50 passed • 4 skipped • 664s

Status	Count
✅ Passed	50
❌ Failed	0
⚠️ Flaky	1
⏭️ Skipped	4

Tests ran across 4 shards in parallel.

View full report →

[brandon-pereira]

LGTM!