R-66: the box's own address becomes visible (v0.159.0)

Leg A: „Hálózat" card on Beállítások → Rendszer — Helyi cím (LAN),
Hálózati név (only while Megosztás is enabled), Átjáró; live per render,
stored nowhere (S-5), „—" on unavailable.
Leg B: network section in the Debug system dump (interfaces/route/DNS/
lan_address), best-effort per item via the samba-netns door.
Leg C: NetBIOS trap named — Szerver field helper text + a purely lexical
hint on unreachable failures for single-label non-IP names.

Design note: all guest-net reads go through docker exec into the
host-networked felhom-samba container (stacks/guestnet.go, one seam) —
the controller's own netns is the docker bridge, so /proc/net/route etc.
would answer 172.x (the S-2 trap). Red-proofs: A2 gate-drop and C2
lexical-invert both failed as required.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UuFPHmHNrCJj1VhY6QdDMU

REUSE.md

@@ -212,6 +212,8 @@
 | `Manager.sambaUpFn` / `sambaPasswdFn` / `sambaRunFn` / `sambaAddrFn` (func seams) | controller/internal/stacks/manager.go (fields) + samba.go | nil → `composeUp` / `docker exec smbpasswd` (STDIN) / `containerRunning("felhom-samba")` / `docker exec felhom-samba ip -4 -o addr show eth0` | injected in controller/internal/stacks/samba_test.go — the idempotency test asserts the up-seam is called **zero** times when config is unchanged; the passwd seam means no unit test ever handles a real secret or touches docker. **`sambaRunFn` has an EXPORTED setter (`SetSambaRunProbe`)** — internal/web's status-contract tests need a live-container world from another package. `sambaAddrFn` backs `SambaLANAddress()` (v0.151.0); its parse is separately pinned in samba_lanaddr_test.go and it returns "" on any failure — the page omits a line rather than printing a wrong address |
 | `Manager.SambaLANAddress()` | controller/internal/stacks/samba.go | `() string` — the guest's LAN IPv4 for the Megosztás connect card (v0.151.0, S-2) | Read from the SAMBA container's netns (`network_mode: host`), never `net.InterfaceAddrs()` — the controller is on a docker BRIDGE and would answer 172.x (the same trap `setup.DetectLocalIPs` needs `HOST_IP` for). **NEVER cache/persist it** — the guest holds it by DHCP (S-5); callers re-derive per render. `""` = omit the line |
 | `Server.sambaAddrFn` (func seam) | controller/internal/web/server.go (field) + sharing_handlers.go `sambaLANAddress()` | nil → `stackMgr.SambaLANAddress()` | The web-side half of the connect card. Tests inject a COUNTED fn — the fresh-per-render assertion is what stops anyone memoizing a DHCP lease |
+| `Manager.guestNetExecFn` (func seam) + `GuestGateway()` / `GuestNetSnapshot()` | controller/internal/stacks/manager.go (field) + guestnet.go | nil → `docker exec felhom-samba <args>` — ONE seam for all R-66 guest-netns reads (route/link/addr/resolv.conf); tests script canned outputs per argv | guestnet_test.go. **The netns door rule:** the controller's OWN netns is the docker bridge, so any in-process read (`net.Interfaces`, `/proc/net/route`, its own `/etc/resolv.conf` = 127.0.0.11) is the S-2 wrong answer — guest-net reads MUST go through the samba (`network_mode: host`) exec door. Megosztás off ⇒ door closed ⇒ "" / per-item error strings; NEVER substitute an in-process value. Same S-5 law as SambaLANAddress: live per render, never cached/persisted. Parsers (`parseDefaultRoute`, `parseGuestInterfaces`, `parseResolvConf`) are pure + separately pinned |
+| `Server.guestGatewayFn` / `guestNetFn` (func seams) | controller/internal/web/server.go (fields) + sharing_handlers.go accessors | nil → `stackMgr.GuestGateway` / `stackMgr.GuestNetSnapshot` | network_card_test.go — the counted-fn freshness test (2 renders ⇒ 2 resolves) is what stops anyone memoizing a DHCP lease; the Hálózati név row is gated on `smb.Enabled` (red-proven: gate dropped ⇒ \\FELHOM rendered while samba is down) |
 | `sambaEnsureState.consumeIfRunning()` | controller/internal/web/samba_ensure_job.go | serve-once `snapshot()` for terminal `running` only | `/sharing/status` carries a job EDGE (`phase`) and a service LEVEL (`running`) in one envelope — never let a level reach the phase channel, and never re-serve a consumed edge: the client answers `phase=="running"` with `location.reload()`, so both mistakes produce an infinite page reload (S-1/S-4, DIAG-sharing-2026-07-20.md). `failed`/`needs_password`/in-flight are NOT consumed |
 | `infra.SambaHostInterface` | controller/internal/infra/samba.go | the guest LAN nic name (`eth0`) | Single source for smb.conf's `interfaces =`, the container's `FELHOM_IFACE`, and the LAN-address read — if they name different nics, the service and the address the page prints drift apart |
 | `Manager.sambaImgFn` (func seam) | controller/internal/stacks/manager.go (field) + samba.go | nil → `docker image inspect <infra.SambaImage>` | drives the 4b card's pulling-vs-starting decision, which MUST be taken before `compose up` (afterwards the image is always present) |