Enforce network restrictions for IPv6 traffic

[Copilot]

IPv6 egress bypassed runtime network restrictions because only iptables rules were configured. Hosts with AAAA records could ignore allow.net / deny.net.

• Runtime firewall

  • Mirrors per-execution iptables chains to ip6tables.
  • Resolves allowed/denied hosts separately with getent ahostsv4 and getent ahostsv6.
  • Applies deny, allow, default reject, OUTPUT insertion, and teardown for both stacks.

• Lima provisioning

  • Configures the default BAND-DEFAULT lockdown chain for both IPv4 and IPv6.

• Firewall script coverage

  • Updates unit expectations to verify IPv6 chain creation, hostname resolution, and OUTPUT routing.

const FIREWALL_TABLES = [
  { table: "iptables", resolver: "ahostsv4" },
  { table: "ip6tables", resolver: "ahostsv6" },
];

[mrjf]

@copilot resolve the merge conflicts in this pull request

[Copilot]

@copilot resolve the merge conflicts in this pull request

Resolved the merge conflicts in commit 180e39c and pushed the updated branch. I also updated the IPv6 security documentation in 3ff08b7.

[mrjf]

@copilot fix ci

[Copilot]

@copilot fix ci

Fixed in ae695c9 by serializing local Lima band server health/execution access across parallel agent test processes. Local validation passed: runtime unit tests, typecheck, and build.