harden and fix: nftables input chain, sudo, agenix, ZFS, NAT priority ...

- Add inet input_filter table to xlab-gateway (policy drop on WAN)
- Restrict NOPASSWD sudo to ldx only; ylw uses password sudo via wheel
- Restructure secrets.nix with admins list, prepare for ylw ed25519 key
- Add ye-lw21 to trusted-users in common.nix
- Remove contradictory relatime=on when atime=off on rpool
- Fix NAT postrouting priority: filter → srcnat
- Remove duplicate nixpkgs.hostPlatform from xlab-gateway hardware-configuration

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

clamp mss to pmtu fix v6

Update networking.nix

Update networking.nix

add route from subnet to phicomm mgmt

fix gateway itself to .1

xlab-gateway: add ULA route for internal IPv6 reachability ...

Route fd99:23eb:1682::/48 via wg-to-wgnet in main table so
xlab-gateway and LAN clients can reach 10.0.0.1's IPv6
(fd99:23eb:1682::1). Without this, ULA traffic went through
the WAN default route and got dropped.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

refactor xlab-gateway IPv6: /64 SLAAC, scoped policy routing, no NAT66 ...

- Change LAN prefix from fd99:23eb:1682:fd:df::/80 to fd99:23eb:1682:1::/64
- Switch from DHCPv6 stateful to SLAAC (AdvAutonomous on, AdvManagedFlag off)
- Add RDNSS in radvd pointing to fd99:23eb:1682::1
- Scope policy routing rules to LAN sources only (fixes gateway IPv6 breakage)
- Remove NAT66 masquerade on wg-to-wgnet (10.0.0.1 routes fd99:23eb:1682:1::/64 natively)

Co-Authored-By: Claude Opus 4.6 <[email protected]>

fix nftables syntax: use meta nfproto ipv6 in inet table ...

Co-Authored-By: Claude Opus 4.6 <[email protected]>

xlab-gateway: route client IPv6 through wg-to-wgnet ...

- Re-add IPv6 default route (::/0) via wg-to-wgnet in table 1002
- Add NAT66 masquerade on wg-to-wgnet for client ULA→tunnel translation
- Campus WAN has no IPv6 transit; wgnet provides it

Co-Authored-By: Claude Opus 4.6 <[email protected]>

xlab-gateway: fix IPv6 routing, clean up table names ...

- Remove IPv6 default route from freedom table (1002) — wgnet peer
  doesn't forward IPv6, causing TLS resets on outbound connections
- Remove Tsinghua IPv6 throw route (unnecessary without IPv6 default)
- IPv6 now uses native WAN path instead of WireGuard tunnel
- Rename table 1002 from typo 'wg-to-skywme' to 'freedom-wgnet'

Co-Authored-By: Claude Opus 4.6 <[email protected]>

Initial skyworks infrastructure flake ...

Unified NixOS configuration for skydick (storage server) and
xlab-gateway (lab router). Flat module structure with shared
common/users/ssh modules, agenix secrets, disko, and deploy-rs.

Co-Authored-By: Claude Opus 4.6 <[email protected]>