Linux x64 runtime: input recovery candidate

Linux x64 browser runtime: pre-dispatch action recovery

Runtime pinned by released Humanish 0.99.1. Keeps the browser-control connection open
when an action is explicitly rejected before dispatch. Other failure handling
is unchanged. Built with the maintained guest/disk/runtime recipes; the kernel,
Firecracker and pinned browser base are unchanged from the prior x64 release.

The image passed a live Linux Firecracker rejection-and-recovery study. Native
Mac qualification uses the separately published ARM64 image. See runtime-release.json
for the source commit, immutable image identity and exact archive checksums.

Source parts contain matching Debian sources, guest/runner notices, kernel and
Firecracker sources/configuration, and the Humanish source archive. Reassemble:

sha256sum -c SHA256SUMS
cat runtime-sources.tar.gz.part* > runtime-sources.tar.gz
tar -tzf runtime-sources.tar.gz

Reassembled source archive SHA-256:
5bb0cfef9d25ee26e33dcaef053a13f2217077baeb02a7abb61b521a57515691.
Runtime tags do not publish the npm package. This asset set remains immutable.