refactor: share timeline and formatting for the active 2.x cohort

Backport the qualified Charts92 lane/formatter consolidation for actual Sandbox UI/Core/Discovery consumers that declare Charts2 peers. Preserve every existing 2.x Waterfall export and the public2.0.23 phone title fix; optional Root formatter exports let consumers delete duplicate formatters. Same production implementation as public3.0.1, with native qualification against2.0.23 static bytes and all20 browser cells plus retained53-row waterfall in progress. The maintained release action names Sandbox UI2.0.20 as the live older-line consumer. No new dependencies.

Run ID: run_d6a451eac952679e802d772b0104ffcb