Part of Phase 1 (Sub-1c): Move trace timeline layout prefs to Zustand

[Parship12]

Which problem is this PR solving?

• Resolves part of Tracking: ADR 0004 Migrate from Redux to Zustand + TanStack React Query #3657

Description of the changes

• Before these changes, the code had one place (duck.ts) that was responsible for three things: storing layout settings (column widths, panel mode, etc.) in Redux, saving those settings to localStorage (so they survive page refresh), reading from localStorage on startup to restore our preferences. This is too much responsibility in one place. The goal of this PR(sub-pr 1) is to move the localStorage responsibility into a new Zustand store.
• Added trace-timeline-store.ts + tests; updates TracePage, TraceTimelineViewer, duck and related tests.
• Matched the migration plan: client UI prefs in Zustand, we now have a clear path to simplify Redux in future PRs.
• Our planning for 1c is like:
  • Sub-PR 1 -> Layout prefs (DONE)
  • Sub-PR 2 -> collapse/detail
  • Sub-PR 3 -> Hover
  • Sub-PR 4 -> remove tracking middleware + delete duck.ts

How was this change tested?

• Unit testing
• Manual testing:
  • Span name column width: Refresh the page -> width should feel the same
  • Side panel mode: Refresh -> mode should stick (detailPanelMode in localStorage)
  • Timeline bars visible: Refresh -> preference should be there (timelineVisible in localStorage)
  • Side panel width: Refresh -> should be remembered (sidePanelWidth in localStorage)

Checklist

• I have read https://github.com/jaegertracing/jaeger/blob/main/CONTRIBUTING_GUIDELINES.md
• I have signed all commits
• I have added unit tests for the new functionality
• I have run lint and test steps successfully: make lint test

AI Usage in this PR (choose one)

See AI Usage Policy.

• None: No AI tools were used in creating this PR
• Light: AI provided minor assistance (formatting, simple suggestions)
• Moderate: AI helped with code generation or debugging specific parts
• Heavy: AI generated most or all of the code changes

[codecov]

Codecov Report

❌ Patch coverage is 92.55319% with 7 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.22%. Comparing base (6f319e2) to head (bf77106).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...kages/jaeger-ui/src/stores/trace-timeline-store.ts	93.93%	3 Missing and 1 partial ⚠️
...components/TracePage/TraceTimelineViewer/index.tsx	81.25%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3719      +/-   ##
==========================================
+ Coverage   89.21%   89.22%   +0.01%     
==========================================
  Files         330      331       +1     
  Lines        9889     9970      +81     
  Branches     2568     2591      +23     
==========================================
+ Hits         8822     8896      +74     
- Misses        925      931       +6     
- Partials      142      143       +1     

☔ View full report in Codecov by Sentry.
📢 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.

[yurishkuro]

All changes in this file are similar, but the alternative approach would be to check that the settings DID persist, just in a different storage.

Having said that, detailPanelMode and timelineVisible are absolutely meant to be persisted to local storage as sticky configuration options (user profile style), they are not supposed to be lost when UI reloads.

[yurishkuro]

btw a future enhancement: #3720

[Parship12]

the tests are edited, just to stop them from failing.

The localStorage persistence is still there, it's now handled by useTraceTimelineStore, which is tested in src/stores/trace-timeline-store.test.ts.

The duck tests for these 4 actions are temporary, the duck itself will be deleted in next sub-PRs along with the remaining redux state. At that point, the only persistence tests will be the ones in trace-timeline-store.test.ts

[Parship12]

btw a future enhancement: #3720

our Zustand store is already a good foundation for it.