doc: beast enabled and neuron disabled on all mining hosts before launch

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CBgs2nSi4H2mdh8kD8vMX5

doc/mainnet-cutover.md

@@ -40,8 +40,12 @@ on mainnet — decided 2026-09-09.
    Validate waits for the miner to connect and for the hash counter to move.
    A wrong `<id>` shows within a minute as a restart loop on benjy and
    quadbrat (permanent connection error on certificate mismatch).
-4. **beast** (if joining): stop `neuron.service` on beast, uncomment the beast
-   row in quantus/miner's deploy matrix, merge; the push deploys it.
+4. **beast**: done before launch (06:15 UTC). neuron (cortex inference) is
+   stopped and disabled on benjy, quadbrat and beast — on benjy it had been
+   halving the hashrate for hours at a time since 6 September — and beast is
+   in quantus/miner's deploy matrix, bob's miner list and the scrape targets.
+   Re-enabling inference on any of them is a deliberate step, not a reboot
+   side effect.
 5. **Commit the values** so push-triggered deploys keep them: in lair/quantus
    `deploy.yaml` set `CHAIN: <id>`, `NODE_VERSION`, `CHAINSPEC_URL`,
    `EXPECTED_GENESIS`, `BOOTNODES`; in quantus/miner `deploy.yaml` set