[build-tools] upload maestro screenshots

[hSATAC]

Depends on https://github.com/expo/universe/pull/28185 — www must persist the artifact metadata this PR sends.

Why

Surface Maestro per-flow failure screenshots in the workflow Maestro test results UI, shown next to the failing test-case row. Part of ENG-19036.

How

• build-tools: After each Maestro attempt (junit output only), harvest failure screenshots from the debug dirs, then reduce to what the UI actually surfaces: a flow that failed on every attempt uploads only its final-attempt screenshot, while a flaky/mixed flow keeps every failed-attempt screenshot (classified from the per-attempt JUnit pass/fail, not screenshot counts). The kept screenshots upload as workflow artifacts carrying metadata (kind, flowName, attemptIndex, capturedAtMs) that the website matches to the corresponding test-case result. Best-effort and verdict-neutral: errors are logged rather than thrown, and uploads are capped at 30 per job.
• worker: Thread an optional metadata field through the artifact upload path (uploadArtifact → uploadWorkflowArtifactAsync → createUploadSessionAsync) so it reaches www.

Test Plan

Unit tests added/updated (maestroScreenshots.test.ts, maestroTests.test.ts), all passing in CI — covering filename parsing, the mtime/capturedAt harvest gating, the pure-vs-flaky reduction (final-only for all-failed flows, every attempt for flaky), the 30-upload cap, upload-before-failure-throw, and per-item error swallowing.

[linear-code]

ENG-19036

[codecov]

Codecov Report

❌ Patch coverage is 95.91837% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 58.55%. Comparing base (84015eb) to head (173cd06).

Files with missing lines	Patch %	Lines
...ld-tools/src/steps/functions/maestroScreenshots.ts	93.75%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3872      +/-   ##
==========================================
+ Coverage   58.46%   58.55%   +0.09%     
==========================================
  Files         922      923       +1     
  Lines       40237    40332      +95     
  Branches     8475     8490      +15     
==========================================
+ Hits        23520    23611      +91     
- Misses      16621    16625       +4     
  Partials       96       96              

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[hSATAC]

• [build-tools] add metadata to eas/upload_artifact #3878
• [build-tools] upload maestro screenshots #3872 👈 (View in Graphite)
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[github-actions]

Subscribed to pull request

File Patterns	Mentions
**/*	@douglowder

Generated by CodeMention

[sjchmiela]

let's remember to drop any additional complexity as soon as we decide to drop the extra support for <2.5?

or maybe we want to do it already?

[hSATAC]

I have a Linear ticket for that.

Around 75% of users are on 2.6+ today. If we drop the old path now, ~25% of users would lose these features immediately.

I was thinking something closer to 90%+ adoption before removing it, but happy to discuss.

[github-actions]

⏩ The changelog entry check has been skipped since the "no changelog" label is present.