Editor Benchmarks Live Results Viewer

Goal

Fix live-results composition in the editor-benchmarks viewer, keep fixture naming honest, and verify the browser surface.

Phases

• Search existing learnings and current viewer/data files
• Fix live/seeding composition and fixture naming
• Rebuild artifacts and verify browser/app shells

Notes

• Work is primarily in ../editor-benchmarks
• Root app should stay viewer-only
• No new benchmark lanes until live results render cleanly
• Fixed the root viewer so live contract rows and snapshot rows render together instead of blanking the table.
• Renamed the fake table-heavy-10k fixture to table-heavy-480-cells.
• The contract runner now isolates each benchmark in its own page and has preview-target scripts.
• The contract runner now uses per-lane sample counts and timeout budgets for the heavy 10k lanes.
• Production preview runs are now completing cleanly.
• Current live rich-markdown snapshot:
  • Plate 03_mount-10k: ~32301 ms
  • Slate 03_mount-10k: ~438 ms
  • Plate 10_type-middle: ~25 ms
  • Slate 10_type-middle: ~26 ms
• So the viewer/runners are healthy now; the remaining problem is the actual Plate 10k mount surface on the richer markdown fixture.