feat: host-agnostic LAN access (base) + fork/recall in pi variants

Item A — LAN access (base image):
- New rootfs/usr/local/lib/opencode-devbox/setup-lan-access.sh, invoked
  non-fatally from entrypoint-user.sh. On VM-backed hosts (macOS OrbStack /
  Docker Desktop, detected via host.docker.internal) it generates a writable
  ~/.ssh-local/config that uses the host as an SSH jump to reach LAN peers;
  no-op on native Linux. Ships the mechanism (generic 'host' jump alias),
  not policy (targets stay in the user's bind-mounted ~/.ssh/config).
- New env knobs: DEVBOX_LAN_ACCESS (auto|jump|off), HOST_SSH_USER,
  DEVBOX_HOST_ALIAS. dssh/dscp aliases in .bash_aliases (guarded).

Item B — pi-fork (fork) + pi-observational-memory (recall) in pi variants:
- Dockerfile.variant clones both elpapi42 repos to /opt and runs npm install
  there at build time (local-path 'pi install' does not npm-install, so deps
  must be present to load). New args PI_FORK_REPO/REF, PI_OBSMEM_REPO/REF.
- entrypoint-user.sh registers them at runtime via 'pi install /opt/<pkg>'
  (instant, in-place, idempotent; tools bind on next pi start).
- CI resolve-versions resolves each repo's master HEAD to a commit SHA and
  passes PI_FORK_REF/PI_OBSMEM_REF — same cache-hit guard as PI_VERSION.
- smoke-test asserts /opt clones + node_modules + settings.json registration;
  size thresholds bumped (with-pi 2700->2900, omos-with-pi 3700->3900).

Versions unchanged (opencode 1.15.13, pi 0.78.0 — both still latest).
Docs: README LAN section + env table, .env.example, AGENTS.md, CHANGELOG.
Plan recorded in docs/plan-lan-access-and-pi-extensions.md.

CHANGELOG.md

@@ -8,7 +8,28 @@ Tags follow `v{opencode_version}[letter]` — bare tag for the first build on a
 
 ## Unreleased
 
-_(no changes since v1.15.13)_
+### Added: host-OS-agnostic LAN access (base image)
+
+The container can now reach LAN peers that the **host** can reach, regardless of host OS — addressing the macOS/Docker-Desktop limitation where a container in the Linux VM cannot see the host's directly-attached LAN.
+
+- New `rootfs/usr/local/lib/opencode-devbox/setup-lan-access.sh`, invoked (non-fatally) by `entrypoint-user.sh` on every start.
+- **Detection:** on VM-backed hosts (macOS OrbStack / Docker Desktop, Windows Docker Desktop — detected via `host.docker.internal` resolution) it generates a writable `~/.ssh-local/config` that uses the host as an SSH **jump**. On native Linux Docker (LAN reachable directly) it is a **no-op**.
+- **Mechanism, not policy:** ships a generic `host` (alias `mac`) jump entry + a generated jump key in the writable `~/.ssh-local/` sidecar (necessary because `~/.ssh` is bind-mounted read-only). Your own targets stay in your bind-mounted `~/.ssh/config` (add `ProxyJump host`), pulled in via `Include ~/.ssh/config`.
+- New env knobs: `DEVBOX_LAN_ACCESS` (`auto`|`jump`|`off`, default `auto`), `HOST_SSH_USER`, `DEVBOX_HOST_ALIAS`. When `HOST_SSH_USER` is unset the entrypoint prints the public key to authorize on the host.
+- New `dssh` / `dscp` aliases in `.bash_aliases` (wrap `ssh -F ~/.ssh-local/config`), guarded so they only appear when the jump config was generated.
+- Because this touches `Dockerfile.base` inputs (`rootfs/`, `entrypoint-user.sh`), the base image rebuilds and `base-latest` advances.
+
+### Added: pi-fork (`fork`) + pi-observational-memory (`recall`) in pi variants
+
+The `with-pi` and `omos-with-pi` variants now bake in two pi extensions from `github.com/elpapi42`:
+
+- `Dockerfile.variant` clones both repos to `/opt/pi-fork` and `/opt/pi-observational-memory` and runs `npm install` there at **build** time (a local-path `pi install` does not npm-install, so deps must be present for the extension to load).
+- `entrypoint-user.sh` registers them at runtime via `pi install /opt/<pkg>` (instant, in-place, idempotent; `fork`/`recall` tools bind on the next pi start).
+- CI (`resolve-versions`) resolves the `master` HEAD of each repo to a concrete commit SHA and passes it as `PI_FORK_REF` / `PI_OBSMEM_REF` build-args — same registry-buildcache cache-hit guard used for `PI_VERSION` / `OMOS_VERSION`.
+- New build-args: `PI_FORK_REPO`, `PI_FORK_REF`, `PI_OBSMEM_REPO`, `PI_OBSMEM_REF`.
+- Smoke test asserts the `/opt` clones + baked `node_modules` exist and that both packages register in `settings.json`. Size thresholds bumped: `with-pi` 2700→2900 MB, `omos-with-pi` 3700→3900 MB (fork's `@earendil-works` peer deps add ~150 MB).
+
+_Versions unchanged: opencode-ai `1.15.13`, pi `0.78.0` (both still latest at time of writing)._
 
 ## v1.15.13 — 2026-05-29