85acb9ab70
- RpcClient: when stdout closes before ready, race child.exited (which settles only after ptree drains the stderr tail for nonzero exits) for 250ms before rejecting, so the earlier-registered exit watcher rejects with the real stderr text instead of an empty 'Stderr:'. - mock-rpc-agent fixture: await the stderr pipe write callback before process.exit so failure text cannot be dropped unflushed. - sdk-tool-activation: restore the default extension-handler budget once the intentionally stalled activation times out, so full-suite machine load cannot also time out the genuine recovery registration. Both tests flaked only under concurrent full-suite chunk load; 10 concurrent stress runs pass post-fix.