Function gdn_woa_enabled 

pub fn gdn_woa_enabled() -> bool

2026-09-25: Write-on-accept K=4 batched verify. Off unless METRALE_GDN_WOA=1. With it off the parent wy4 kernel runs, the fold in woa.rs returns Ok(false), and the accept path (async_chkpt.rs) restores h for every K.

Off by default on a measurement: on GB10 on 2026-09-18, concurrency sweeps with it on had the semantic-loop watchdog fire at C=4 (4 fires) where runs with it off had none, and failed the gate; C=16..128 were unaffected. The cause inside the arm is not identified.

Public so the serve can tell the gamma resolver whether the K=4 rung has its kernel.