feat(pfi-gx10): stage ERP-seat SFT run 3c — verified, not launched

Rehome run 3c from ana-ml2 to pfi-gx10 unchanged: same corpus, base,
recipe and hyperparameters, different host. Slower (~13.3 h vs ~2.5 h)
and correct — an Anaheim breaker trip costs a 40-minute drive each way
and 13 hosts down, three of them SureFire client machines, while the
GX10 is a ~240 W appliance at NH3 that can take nothing else down.

Verified rather than assumed, because ana-ml2 ran transformers 5.15.1
on x86-64 and this box runs 5.16.1 on aarch64 — the silent
backend-delta class that has already voided conclusions here:

  - both 49 GB base shards sha256-match ana-ml2's (size equality is a
    weaker claim and was already true)
  - a full encode was run into a throwaway dir and the encoded corpus
    compared byte-for-byte: 197,360,233 B, sha256 c08bb1fe2ecb0be3,
    identical. Every aggregate matched too. That verified artifact is
    what the run will train on — it is seeded into run-03c/encode-cache
  - the harness's own suite: 122 passed on aarch64
  - the config generator asserts key-by-key that no non-path value
    differs from run-03c.json

The encode-cache filename differs by design (base_model_path is part of
the key) — an input hash, not an output hash. Documented so it is not
misread as drift, or "fixed" by faking /tank on this box.

Corpus is copied to local NVMe; the box mounts no NFS. nh3-nas is now on
the same subnet, which makes mounting it tempting and still wrong under
a 13 h unattended run.

The launcher refuses on a live pidfile rather than a pgrep: `pgrep -f
erp_sft_harness` invoked over ssh matches the invoking shell's own argv.
That self-match cost a shell during staging.

Not launched. 13.3 h is the operator's call.

persistent-memory.md

@@ -112,8 +112,13 @@ _As of 2026-09-03 — **nothing is mid-action; the session closed clean.** Every
 item below is a live commitment or a known-open risk, not work in progress._
 
 - **Nothing is running.** No training, no deploys pending, no background jobs.
-  35 commits sit unpushed on `main` — all docs, runbooks, memory and two
-  scripts; push is the operator's call.
+  Commits sit unpushed on `main` — all docs, runbooks, memory and scripts;
+  push is the operator's call.
+
+- **Run 3c is staged on pfi-gx10 and awaiting the operator's go.** Everything is
+  verified and one command away (`ssh infra-ops@10.100.50.60
+  '~/erp-tune/launch-run-03c.sh'`); ~13.3 h once started. Its train loop is the
+  one piece never exercised on sm_121 — watch the first three minutes.
 
 - **`web_search` needs a session restart to appear.** The SearXNG MCP server is
   registered at user scope and `claude mcp list` reports it Connected, but MCP
@@ -145,6 +150,7 @@ item below is a live commitment or a known-open risk, not work in progress._
 
 ## Recent decisions
 
+- `[2026-09-03]` **Run 3c is STAGED on pfi-gx10 and deliberately NOT launched** — the launch is a 13.3 h commitment and the operator stood this port down once already. Base shards AND the encoded corpus sha256-verified identical to ana-ml2's, so the transformers 5.15.1→5.16.1 / x86-64→aarch64 delta is *measured* inert. ⚠ The encode-cache FILENAME differs by design (`base_model_path` is in the key) — input hash, not output. ⚠ Tripped the `pkill -f` ssh self-match again; the launcher guards on a pidfile because of it. → `persistent-memory.d/2026-09-03-gx10-run3c-staged.md`
 - `[2026-09-03]` **SearXNG returned ZERO results for every query while reporting `healthy` for 7 days — 4.5 months stale.** Moved to nh3-docker (residential egress beats the colo's CAPTCHA-gated 38.120.12.42), updated, and exposed to every CC session as the user-scope `web_search` MCP tool. ⚠ `/healthz` cannot tell you whether search works. → `persistent-memory.d/2026-09-03-searxng-nh3-move.md`
 - `[2026-09-03]` **pfi-gx10 racked: VLAN 50 via a DHCP RESERVATION on the UDM, not a host static — operator ruling, so the box stays portable.** ⚠ The racked port arrived on the NATIVE VLAN; ⚠ `port_overrides` is a whole-array PUT; ⚠ prove inter-VLAN routing with `ping -I <wired>` BEFORE downing the Wi-Fi escape hatch. Now single-path. → `persistent-memory.d/2026-09-03-gx10-rack-network.md`
 - `[2026-09-03]` **Three Macs onboarded (mini / Air / Studio) with infra-ops, NOPASSWD sudo, rotated+vaulted passwords and `dsh` on device-scoped keys — and the fourth is `scripts/provision-mac-dsh.sh`, not a fourth hand-run.** ⚠ `sudo -u` keeps the CALLER's `$HOME` and nearly wiped a working install; ⚠ a wrong USERNAME is indistinguishable from a wrong password. → `persistent-memory.d/2026-09-03-mac-fleet-dsh.md`