For Doyle's docs close PR — replace IR-142's Status line; preserve its original RCA and negative-control history.

- **Status:** DONE — symmetric barrier shipped in [core PR #233](https://github.com/BigscreenVR/spt-bs-core/pull/233); acceptance met on [golden #4, run 35372054865 attempt 1](https://github.com/BigscreenVR/spt-bs-core/actions/runs/35372054865/attempts/1), candidate `7e35ba43a621507b97713619e5229eab790f5547`, ruled by doyle `U2QKULYY`. On 2026-09-18, twohost-a started **17:50:15Z**, completed **18:06:39Z SUCCESS**; twohost-b started **17:50:14Z**, completed **18:21:09Z SUCCESS**: **1s start skew, both green**. Golden #3 remains NOT_MET (27m08s INTERLEAVE-SKEW); the barrier is not a cross-workflow runner reservation. Attempt 2 pairing is bonus evidence, not a closure precondition. Receipt: `.spt/preserved/307/twohost-barrier/golden4-acceptance.json`.

The entry's stale 'Acceptance, not yet claimed' bullet should be reconciled in the same docs close PR with this measured acceptance; retain the single-slot/cross-workflow contention boundary.