Long runs display total minutes, such as `419m 50s`, which is hard to read.

Show `6h 59m 50s` instead. Web, desktop, and mobile use the shared formatter for long live, completed, and stopped runs.

## Verification

- 210 tests pass with `vp test run packages/shared/src/orchestrationTiming.test.ts apps/web/src/components/chat/MessagesTimeline.logic.test.ts apps/mobile/src/lib/threadActivity.test.ts`.
- Shared, web, and mobile typechecks pass.
- Changed-file lint and formatting pass, with existing lint warnings.
- Browser verification and screenshots skipped at Theo's request.

Created with GPT-6 Astra (preview) in Codex.